diff --git a/ROADMAP.md b/ROADMAP.md
index 7c59c1f6a6..d29ac5c752 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -12,7 +12,6 @@ the codebase, you are probably right to stay away.
   and WSL all need coverage.
 
 - Integration audit: do integrations even work? Confirm what works, what needs setup docs, and what should be removed or hidden. 
-- Self-host troubleshooting cookbook. Document the weird 30-second fixes that otherwise become 30-minute searches: Dovecot cleartext auth for local stacks, ntfy Android Instant Delivery for non-ntfy.sh servers, clipboard limits on plain-HTTP Tailscale URLs, Radicale collection URLs, and similar traps.
 - Cookbook reliability on other computers. This is probably the area most likely to need work across different machines, GPUs, drivers, shells, and Python environments.
 - Cookbook SGLang support across platforms. Make sure SGLang setup/serve works
   predictably on Linux, Windows/WSL, macOS where possible, Docker, and common
diff --git a/app.py b/app.py
index a89f80143c..38c848e0bd 100644
--- a/app.py
+++ b/app.py
@@ -655,7 +655,12 @@ async def _stop_background():
 # Sessions
 from routes.session_routes import setup_session_routes
 session_config = {"REQUEST_TIMEOUT": REQUEST_TIMEOUT, "OPENAI_API_KEY": OPENAI_API_KEY, "SESSIONS_FILE": SESSIONS_FILE}
-app.include_router(setup_session_routes(session_manager, session_config, webhook_manager=webhook_manager))
+app.include_router(setup_session_routes(
+    session_manager,
+    session_config,
+    webhook_manager=webhook_manager,
+    upload_handler=upload_handler,
+))
 
 # Admin Danger Zone wipes (Settings → System → Danger Zone)
 from routes.admin_wipe_routes import setup_admin_wipe_routes
@@ -684,7 +689,7 @@ async def _stop_background():
 
 # History
 from routes.history.history_routes import setup_history_routes
-app.include_router(setup_history_routes(session_manager))
+app.include_router(setup_history_routes(session_manager, upload_handler=upload_handler))
 
 # Search
 from routes.search_routes import setup_search_routes
@@ -763,7 +768,7 @@ async def _stop_background():
 
 # Calendar (CalDAV)
 from routes.calendar_routes import setup_calendar_routes
-calendar_router = setup_calendar_routes()
+calendar_router = setup_calendar_routes(upload_handler=upload_handler)
 app.include_router(calendar_router)
 
 # Shell (user-facing command execution)
@@ -826,7 +831,7 @@ async def _stop_background():
 
 # Notes (Google Keep-style notes/todos)
 from routes.note_routes import setup_note_routes
-app.include_router(setup_note_routes(task_scheduler))
+app.include_router(setup_note_routes(task_scheduler, upload_handler=upload_handler))
 
 # Email
 from routes.email_routes import setup_email_routes
@@ -1043,7 +1048,7 @@ async def _startup_mcp_connections():
         except BaseException as e:
             logger.warning(f"Built-in MCP registration failed (non-critical): {type(e).__name__}: {e}")
         try:
-            await asyncio.wait_for(mcp_manager.connect_all_enabled(), timeout=20)
+            await mcp_manager.connect_all_enabled()
         except asyncio.TimeoutError:
             logger.warning("User MCP startup timed out (non-critical)")
         except BaseException as e:
diff --git a/core/database.py b/core/database.py
index ade995871a..a9ad90b8b7 100644
--- a/core/database.py
+++ b/core/database.py
@@ -3,13 +3,16 @@
 import sqlite3
 from datetime import datetime, timezone
 from pathlib import Path
+from typing import Optional
+from urllib.parse import unquote, urlparse
 from sqlalchemy import event, create_engine, Column, String, Text, Boolean, DateTime, Integer, ForeignKey, JSON, Index, func, text
-from sqlalchemy.engine import Engine
+from sqlalchemy.engine import Engine, make_url
 from sqlalchemy.types import TypeDecorator
 from sqlalchemy.ext.declarative import declarative_base, declared_attr
 from sqlalchemy.orm import relationship, sessionmaker, backref
 
 from src.runtime_paths import get_app_root
+from core.platform_compat import safe_chmod, IS_WINDOWS
 
 logger = logging.getLogger(__name__)
 
@@ -42,12 +45,28 @@ def _default_database_url() -> str:
 
 
 def _normalize_sqlite_url(url: str) -> str:
-    if not url.startswith("sqlite:///"):
+    """Resolve relative ordinary SQLite paths without rewriting URI filenames."""
+    try:
+        parsed = make_url(url)
+    except Exception:
+        return url
+
+    if parsed.get_backend_name() != "sqlite":
         return url
-    db_path = url.replace("sqlite:///", "", 1)
-    if db_path == ":memory:" or os.path.isabs(db_path):
+
+    db_path = parsed.database
+    if (
+        not db_path
+        or db_path == ":memory:"
+        or str(db_path).lower().startswith("file:")
+        or os.path.isabs(str(db_path))
+    ):
         return url
-    return f"sqlite:///{(Path(get_app_root()) / db_path).resolve().as_posix()}"
+
+    absolute_path = (Path(get_app_root()) / str(db_path)).resolve().as_posix()
+    return parsed.set(database=absolute_path).render_as_string(
+        hide_password=False
+    )
 
 
 # Get database URL from environment, default to SQLite in DATA_DIR
@@ -59,6 +78,59 @@ def _normalize_sqlite_url(url: str) -> str:
     connect_args={"check_same_thread": False} if "sqlite" in DATABASE_URL else {}
 )
 
+
+# Sidecar files SQLite can create next to the main DB. -journal is the default
+# rollback journal; -wal/-shm appear once WAL is enabled. Each can hold copies of
+# secret-bearing pages, so they get the same 0o600 lockdown as the DB itself.
+_SQLITE_SIDECARS = ("-journal", "-wal", "-shm")
+
+
+def _sqlite_db_path(url) -> Optional[str]:
+    """Return the filesystem path for a file-backed SQLite URL.
+
+    SQLite query parameters such as ``mode=memory`` only affect filename
+    semantics when SQLAlchemy enables URI handling with ``uri=true``. Ordinary
+    file URLs must therefore remain file-backed even when they contain a query
+    parameter named ``mode``.
+
+    For SQLite ``file:`` URIs, an empty authority or ``localhost`` identifies a
+    local path. Other authorities are retained as UNC-style paths.
+    """
+    if url.get_backend_name() != "sqlite":
+        return None
+
+    db_path = url.database
+    if not db_path or db_path == ":memory:":
+        return None
+
+    db_path = str(db_path)
+    query = {
+        str(key).lower(): str(value).strip().lower()
+        for key, value in dict(getattr(url, "query", {}) or {}).items()
+    }
+    uri_enabled = query.get("uri") in {"1", "true", "yes", "on"}
+    is_file_uri = db_path.lower().startswith("file:")
+
+    if not uri_enabled or not is_file_uri:
+        return db_path
+
+    if (
+        db_path.lower().startswith("file::memory:")
+        or query.get("mode") == "memory"
+    ):
+        return None
+
+    parsed = urlparse(db_path)
+    fs_path = parsed.path or ""
+    if not fs_path or fs_path == ":memory:":
+        return None
+
+    authority = parsed.netloc
+    if authority and authority.lower() != "localhost":
+        fs_path = f"//{authority}{fs_path}"
+
+    return unquote(fs_path)
+
 # Create session factory
 SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
 
@@ -1819,6 +1891,41 @@ def init_db():
     """
     _migrate_model_endpoints()
     Base.metadata.create_all(bind=engine)
+    # Lock the DB file (and any SQLite sidecars) to 0o600 — it holds bearer-token
+    # + bcrypt hashes and encrypted provider keys. POSIX only; safe_chmod no-ops
+    # on Windows (ACL-restricted profile dir) and the path helper returns None for
+    # Postgres / in-memory. Must stay AFTER create_all: the file is born here at
+    # the umask default, and nothing below resets the mode. The path comes from
+    # engine.url (SQLAlchemy's parsed URL), so a driver-qualified or query-tagged
+    # DATABASE_URL still resolves to the real file instead of slipping through.
+    db_path = _sqlite_db_path(engine.url)
+    if db_path is not None:
+        # Fail closed-loud on the main file: this is the only access control on
+        # it, so if the chmod genuinely fails (read-only FS, foreign owner) an
+        # operator should hear about it. safe_chmod also returns False as a
+        # Windows no-op, so guard on IS_WINDOWS to avoid a spurious warning there.
+        if not safe_chmod(db_path, 0o600) and not IS_WINDOWS:
+            logger.warning(
+                "Could not restrict %s to 0o600; it holds secrets and may be "
+                "world-readable. Check filesystem permissions and ownership.",
+                db_path,
+            )
+        # Re-lock any sidecars present at startup. New ones inherit the main
+        # file's mode (now 0o600, since we set it first), and they're usually
+        # absent here, but a stale -wal/-shm/-journal left by an older 0o644
+        # install could still expose secret pages. Absent sidecars are the
+        # normal case, not an error — only a failed chmod warrants a warning.
+        for suffix in _SQLITE_SIDECARS:
+            sidecar = db_path + suffix
+            if (
+                os.path.exists(sidecar)
+                and not safe_chmod(sidecar, 0o600)
+                and not IS_WINDOWS
+            ):
+                logger.warning(
+                    "Could not restrict %s to 0o600; it may expose DB pages.",
+                    sidecar,
+                )
     _migrate_add_hidden_models_column()
     _migrate_add_cached_models_column()
     _migrate_add_pinned_models_column()
@@ -1904,6 +2011,20 @@ def _migrate_chat_messages_fts():
     conn = None
     try:
         conn = sqlite3.connect(db_path)
+        fts_content_expr_new = (
+            "CASE WHEN instr(COALESCE(new.content, ''), ';base64,') > 0 "
+            "OR instr(COALESCE(new.content, ''), 'data:image/') > 0 "
+            "OR instr(COALESCE(new.content, ''), 'data:audio/') > 0 "
+            "THEN '[inline media omitted from search index]' "
+            "ELSE COALESCE(new.content, '') END"
+        )
+        fts_content_expr_cm = (
+            "CASE WHEN instr(COALESCE(cm.content, ''), ';base64,') > 0 "
+            "OR instr(COALESCE(cm.content, ''), 'data:image/') > 0 "
+            "OR instr(COALESCE(cm.content, ''), 'data:audio/') > 0 "
+            "THEN '[inline media omitted from search index]' "
+            "ELSE COALESCE(cm.content, '') END"
+        )
         try:
             conn.execute("CREATE VIRTUAL TABLE IF NOT EXISTS temp._odysseus_fts5_probe USING fts5(content)")
             conn.execute("DROP TABLE IF EXISTS temp._odysseus_fts5_probe")
@@ -1912,7 +2033,7 @@ def _migrate_chat_messages_fts():
             return
 
         conn.executescript(
-            """
+            f"""
             CREATE VIRTUAL TABLE IF NOT EXISTS chat_messages_fts USING fts5(
                 content,
                 message_id UNINDEXED,
@@ -1920,10 +2041,14 @@ def _migrate_chat_messages_fts():
                 role UNINDEXED
             );
 
+            DROP TRIGGER IF EXISTS chat_messages_fts_ai;
+            DROP TRIGGER IF EXISTS chat_messages_fts_ad;
+            DROP TRIGGER IF EXISTS chat_messages_fts_au;
+
             CREATE TRIGGER IF NOT EXISTS chat_messages_fts_ai
             AFTER INSERT ON chat_messages BEGIN
                 INSERT INTO chat_messages_fts(content, message_id, session_id, role)
-                VALUES (COALESCE(new.content, ''), new.id, new.session_id, new.role);
+                VALUES ({fts_content_expr_new}, new.id, new.session_id, new.role);
             END;
 
             CREATE TRIGGER IF NOT EXISTS chat_messages_fts_ad
@@ -1935,14 +2060,14 @@ def _migrate_chat_messages_fts():
             AFTER UPDATE ON chat_messages BEGIN
                 DELETE FROM chat_messages_fts WHERE message_id = old.id;
                 INSERT INTO chat_messages_fts(content, message_id, session_id, role)
-                VALUES (COALESCE(new.content, ''), new.id, new.session_id, new.role);
+                VALUES ({fts_content_expr_new}, new.id, new.session_id, new.role);
             END;
             """
         )
         conn.execute(
-            """
+            f"""
             INSERT INTO chat_messages_fts(content, message_id, session_id, role)
-            SELECT COALESCE(cm.content, ''), cm.id, cm.session_id, cm.role
+            SELECT {fts_content_expr_cm}, cm.id, cm.session_id, cm.role
             FROM chat_messages cm
             WHERE NOT EXISTS (
                 SELECT 1 FROM chat_messages_fts fts
@@ -1950,6 +2075,7 @@ def _migrate_chat_messages_fts():
             )
             """
         )
+        _scrub_legacy_chat_message_fts_media(conn)
         conn.commit()
     except Exception as e:
         logging.getLogger(__name__).warning(f"chat_messages FTS migration failed: {e}")
@@ -1960,6 +2086,37 @@ def _migrate_chat_messages_fts():
             pass
 
 
+def _scrub_legacy_chat_message_fts_media(conn) -> None:
+    """Replace already-indexed inline media rows with searchable text only."""
+    try:
+        from src.attachment_refs import search_index_text
+    except Exception as e:
+        logging.getLogger(__name__).warning(f"chat_messages FTS media scrub skipped: {e}")
+        return
+
+    try:
+        rows = conn.execute(
+            """
+            SELECT id, session_id, role, content
+            FROM chat_messages
+            WHERE instr(COALESCE(content, ''), ';base64,') > 0
+               OR instr(COALESCE(content, ''), 'data:image/') > 0
+               OR instr(COALESCE(content, ''), 'data:audio/') > 0
+            """
+        ).fetchall()
+        for message_id, session_id, role, content in rows:
+            conn.execute("DELETE FROM chat_messages_fts WHERE message_id = ?", (message_id,))
+            conn.execute(
+                """
+                INSERT INTO chat_messages_fts(content, message_id, session_id, role)
+                VALUES (?, ?, ?, ?)
+                """,
+                (search_index_text(content), message_id, session_id, role),
+            )
+    except Exception as e:
+        logging.getLogger(__name__).warning(f"chat_messages FTS media scrub failed: {e}")
+
+
 def _migrate_add_email_smtp_security():
     """Add explicit SMTP security mode for Proton Bridge/custom local SMTP."""
     import sqlite3
diff --git a/core/session_manager.py b/core/session_manager.py
index 491fbc0782..f5024d212c 100644
--- a/core/session_manager.py
+++ b/core/session_manager.py
@@ -16,6 +16,8 @@
 
 from .database import Session as DbSession, ChatMessage as DbChatMessage, Document as DbDocument, SessionLocal, utcnow_naive
 from .models import Session, ChatMessage
+from src.attachment_refs import persistable_message_content
+from src.upload_handler import reserve_message_upload_references
 
 # Re-export singleton accessors from models for convenience
 from .models import set_session_manager_instance, get_session_manager_instance
@@ -72,6 +74,7 @@ class SessionManager:
     def __init__(self, sessions_file: str = None):
         # sessions_file kept for backward compat, not used
         self.sessions: Dict[str, Session] = {}
+        self.upload_handler = None
         self.load_sessions()
 
     # ------------------------------------------------------------------
@@ -230,17 +233,26 @@ def _persist_message(self, session_id: str, message: ChatMessage):
                 logger.warning("Dropping message for deleted session %s", session_id)
                 return
 
+            missing_upload_id = reserve_message_upload_references(
+                getattr(self, "upload_handler", None),
+                getattr(db_session, "owner", None),
+                message.content,
+                message.metadata,
+            )
+            if missing_upload_id:
+                raise ValueError(
+                    f"Referenced upload is no longer available: {missing_upload_id}"
+                )
+
             msg_id = str(uuid.uuid4())
             msg_time = datetime.utcnow()
             if message.metadata is None:
                 message.metadata = {}
             message.metadata.setdefault('timestamp', _message_timestamp_iso(msg_time))
-            # Multimodal content (image/audio attachments) is a list — serialize
-            # to JSON so the Text column can store it.  On reload, _db_to_session
-            # detects the JSON-array prefix and parses it back.
-            _content = message.content
-            if isinstance(_content, list):
-                _content = json.dumps(_content)
+            # Multimodal content may contain provider data URLs for the live
+            # model call. Persist only readable text plus attachment references
+            # so chat_messages/FTS do not duplicate upload bytes.
+            _content = persistable_message_content(message.content, message.metadata)
             db_message = DbChatMessage(
                 id=msg_id,
                 session_id=session_id,
@@ -322,6 +334,28 @@ def replace_messages(self, session_id: str, messages: list) -> bool:
         session = self.get_session(session_id)
         db = SessionLocal()
         try:
+            db_session = db.query(DbSession).filter(DbSession.id == session_id).first()
+            if db_session is None:
+                logger.warning("Cannot replace history for missing session %s", session_id)
+                return False
+
+            # Reserve every incoming attachment before removing any durable
+            # message row. reserve_upload() shares the upload lifecycle lock
+            # with cleanup, so an upload cannot be deleted between this
+            # ownership check/access touch and the replacement transaction.
+            # A failed reservation must leave the existing transcript intact.
+            for message in messages:
+                missing_upload_id = reserve_message_upload_references(
+                    getattr(self, "upload_handler", None),
+                    getattr(db_session, "owner", None),
+                    message.content,
+                    message.metadata,
+                )
+                if missing_upload_id:
+                    raise ValueError(
+                        f"Referenced upload is no longer available: {missing_upload_id}"
+                    )
+
             db.query(DbChatMessage).filter(DbChatMessage.session_id == session_id).delete()
             now = datetime.now(timezone.utc)
             for i, message in enumerate(messages):
@@ -330,15 +364,9 @@ def replace_messages(self, session_id: str, messages: list) -> bool:
                     id=msg_id,
                     session_id=session_id,
                     role=message.role,
-                    # Multimodal content (image/audio attachments) is a list;
-                    # serialize to JSON so the Text column round-trips via
-                    # _parse_msg_content. Storing the raw list let SQLAlchemy
-                    # bind its single-quoted repr, which _parse_msg_content
-                    # cannot parse (it looks for double-quoted "type"), so the
-                    # attachment was destroyed on reload. Mirrors _persist_message.
-                    content=(json.dumps(message.content)
-                             if isinstance(message.content, list)
-                             else message.content),
+                    # Mirrors _persist_message: keep raw media bytes out of the
+                    # persisted transcript and search index.
+                    content=persistable_message_content(message.content, message.metadata),
                     meta_data=json.dumps(message.metadata) if message.metadata else None,
                     timestamp=now + timedelta(microseconds=i),
                 )
@@ -347,12 +375,10 @@ def replace_messages(self, session_id: str, messages: list) -> bool:
                     message.metadata = {}
                 message.metadata["_db_id"] = msg_id
 
-            db_session = db.query(DbSession).filter(DbSession.id == session_id).first()
-            if db_session:
-                db_session.message_count = len(messages)
-                db_session.updated_at = now
-                db_session.last_accessed = now
-                db_session.last_message_at = now
+            db_session.message_count = len(messages)
+            db_session.updated_at = now
+            db_session.last_accessed = now
+            db_session.last_message_at = now
 
             db.commit()
             session.history = list(messages)
diff --git a/docs/attachments.md b/docs/attachments.md
new file mode 100644
index 0000000000..93f9e0ffe1
--- /dev/null
+++ b/docs/attachments.md
@@ -0,0 +1,85 @@
+# Attachment References and Upload Storage
+
+Odysseus stores uploaded bytes once under the configured upload directory and
+passes stable references through chat history, tools, and future artifact work.
+The goal is to avoid duplicating large inline media payloads in
+`chat_messages.content` or the SQLite FTS index.
+
+## Reference Shape
+
+Attachment references use this minimum shape:
+
+```json
+{
+  "type": "attachment_ref",
+  "attachment_id": "32hex-or-32hex.ext",
+  "name": "original-filename.png",
+  "mime": "image/png",
+  "size": 12345,
+  "checksum_sha256": "hex-digest",
+  "created_at": "2026-07-09T12:00:00"
+}
+```
+
+Optional fields such as `width`, `height`, `vision`, `vision_model`, and
+`gallery_id` may be present when the uploader or preprocessing path knows them.
+
+## Persistence
+
+The live model call may still receive provider-specific multimodal blocks for
+the current turn. Persistence is different:
+
+- `chat_messages.content` stores readable text plus compact attachment reference
+  lines, never raw `data:*;base64,...` upload bytes.
+- `chat_messages.metadata.attachments` stores structured attachment reference
+  metadata for UI reloads and future processing.
+- The SQLite FTS migration recreates chat-message FTS triggers so new rows do
+  not index inline media payloads, and it scrubs legacy rows that were already
+  indexed with data URLs.
+
+## Tool Access
+
+Agent/tool context receives upload entries as `attachment_ref` manifests with an
+`odysseus://attachment/<id>` URI and `read_policy: "owner_checked_upload"`.
+
+For compatibility with existing built-in tools, a local `path` may be included
+only after all of these checks pass:
+
+- the upload ID resolves through `UploadHandler.resolve_upload`;
+- the requested owner is allowed to read the upload;
+- the file remains inside the configured upload directory;
+- the file path is inside the tool-readable roots.
+
+External MCP/custom tools should treat the URI and attachment ID as the stable
+contract and request bytes through an owner-checked server path, not by assuming
+host filesystem layout.
+
+## Retention and Deletion
+
+Current retention behavior is conservative:
+
+- uploads are indexed in `uploads.json` with owner, checksum, MIME type, size,
+  and creation time;
+- admin cleanup first scans persisted chat metadata/content, document versions,
+  PDF source markers, gallery hashes, notes, and calendar records for live
+  references;
+- cleanup fails closed if that reference scan cannot complete, and the lower-level
+  cleanup API removes nothing unless it receives a complete reference snapshot;
+- expired, unreferenced uploads are removed during the completed scan, while
+  attachment-bearing writers must first take an owner-checked reservation that
+  serializes with deletion and refreshes the upload's access timestamp;
+- deliberate removal atomically drops matching `uploads.json` rows before deleting
+  the bytes and restores those rows if filesystem removal fails;
+- deleting a chat removes the chat rows but does not immediately delete shared
+  upload bytes, because the same upload may also be referenced by gallery items,
+  documents, duplicate-upload rows, or future artifact records.
+
+There is no distinct artifact table in the current schema. Artifact-like upload
+references persisted in chat or document text are covered by the canonical
+attachment-ID scan; any future artifact store must be added to reference discovery
+before cleanup is allowed to consider its uploads unreferenced.
+
+Cleanup and write reservations share the upload-index lock. This closes the
+scan/write/delete race in the documented single-worker deployment; a future
+multi-process deployment must add an inter-process lock or move lifecycle state
+into the database before enabling destructive cleanup in more than one worker.
diff --git a/routes/calendar_routes.py b/routes/calendar_routes.py
index 81dd48a5b2..6e0ee124c3 100644
--- a/routes/calendar_routes.py
+++ b/routes/calendar_routes.py
@@ -13,8 +13,9 @@
 from dateutil.rrule import rrulestr
 
 from core.database import SessionLocal, CalendarCal, CalendarDeletedEvent, CalendarEvent
-from src.auth_helpers import require_user
+from src.auth_helpers import effective_user, require_user
 from src.upload_limits import read_upload_limited, ICS_MAX_BYTES
+from src.upload_handler import reserve_upload_references
 
 logger = logging.getLogger(__name__)
 
@@ -697,9 +698,18 @@ def _expand_rrule(
 
 # ── Routes ──
 
-def setup_calendar_routes() -> APIRouter:
+def setup_calendar_routes(upload_handler=None) -> APIRouter:
     router = APIRouter(prefix="/api/calendar", tags=["calendar"])
 
+    def _reserve_calendar_uploads(request: Request, *values) -> None:
+        missing_id = reserve_upload_references(
+            upload_handler,
+            effective_user(request),
+            *values,
+        )
+        if missing_id:
+            raise HTTPException(409, f"Referenced upload is no longer available: {missing_id}")
+
     # ── CalDAV multi-account helpers ─────────────────────────────────────────
 
     def _get_caldav_accounts(owner: str) -> list:
@@ -913,7 +923,24 @@ async def test_connection(request: Request):
             '</d:prop></d:propfind>'
         )
         try:
-            async with httpx.AsyncClient(timeout=8.0, follow_redirects=False, trust_env=False) as cx:
+            # Build an SSL context that trusts the operator's custom CA bundle
+            # (SSL_CERT_FILE / REQUESTS_CA_BUNDLE) so self-signed CalDAV servers
+            # pass the pre-flight the same way they pass the real sync.
+            # trust_env=False is kept to block proxy/auth env leakage; the CA
+            # bundle is loaded explicitly instead.
+            import ssl as _ssl
+            _ssl_ctx = _ssl.create_default_context()
+            # Disable VERIFY_X509_STRICT so certs without a keyUsage extension
+            # (common in self-signed setups) are accepted, matching the
+            # requests/urllib3 behavior used by the CalDAV sync path.
+            _ssl_ctx.verify_flags &= ~_ssl.VERIFY_X509_STRICT
+            _ca_bundle = _os.environ.get("SSL_CERT_FILE") or _os.environ.get("REQUESTS_CA_BUNDLE")
+            if _ca_bundle:
+                if _os.path.isfile(_ca_bundle):
+                    _ssl_ctx.load_verify_locations(_ca_bundle)
+                else:
+                    logger.warning("CalDAV test: CA bundle %s not found, using system CAs", _ca_bundle)
+            async with httpx.AsyncClient(timeout=8.0, follow_redirects=False, trust_env=False, verify=_ssl_ctx) as cx:
                 r = await cx.request(
                     "PROPFIND", url,
                     auth=(user, pw),
@@ -1070,6 +1097,7 @@ async def list_events(request: Request, start: str, end: str, calendar: str = ""
     @router.post("/events")
     async def create_event(request: Request, data: EventCreate):
         owner = _require_user(request)
+        _reserve_calendar_uploads(request, data.color, data.description, data.location)
         db = SessionLocal()
         try:
             cal = None
@@ -1131,6 +1159,7 @@ async def create_event(request: Request, data: EventCreate):
     @router.put("/events/{uid}")
     async def update_event(request: Request, uid: str, data: EventUpdate):
         owner = _require_user(request)
+        _reserve_calendar_uploads(request, data.color, data.description, data.location)
         try:
             base_uid = _resolve_base_uid(uid)
         except ValueError as e:
@@ -1224,6 +1253,7 @@ async def delete_event(request: Request, uid: str, scope: str = "series"):
     @router.post("/calendars")
     async def create_calendar(request: Request, name: str = "Imported", color: str = "#5b8abf"):
         owner = _require_user(request)
+        _reserve_calendar_uploads(request, color)
         db = SessionLocal()
         try:
             cal = CalendarCal(
@@ -1246,6 +1276,7 @@ async def create_calendar(request: Request, name: str = "Imported", color: str =
     @router.put("/calendars/{cal_id}")
     async def update_calendar(request: Request, cal_id: str, name: str = None, color: str = None):
         owner = _require_user(request)
+        _reserve_calendar_uploads(request, color)
         db = SessionLocal()
         try:
             cal = _get_or_404_calendar(db, cal_id, owner)
diff --git a/routes/chat_helpers.py b/routes/chat_helpers.py
index cdd204ec26..63c8abc8f8 100644
--- a/routes/chat_helpers.py
+++ b/routes/chat_helpers.py
@@ -17,6 +17,7 @@
 from src.model_context import estimate_tokens
 from src.auth_helpers import effective_user
 from src.prompt_security import untrusted_context_message
+from src.attachment_refs import attachment_ref
 from routes.prefs_routes import _load_for_user as load_prefs_for_user
 
 from fastapi import HTTPException
@@ -418,13 +419,16 @@ def _read_file_can_open(path: str) -> bool:
             except Exception:
                 path = None
 
-        manifest.append({
-            "id": info.get("id") or str(att_id),
-            "name": info.get("name") or info.get("original_name") or str(att_id),
-            "mime": info.get("mime", ""),
-            "size": info.get("size", 0),
+        ref = attachment_ref({**info, "id": info.get("id") or str(att_id)})
+        ref.update({
+            "id": ref["attachment_id"],
+            "uri": f"odysseus://attachment/{ref['attachment_id']}",
+            "read_policy": "owner_checked_upload",
+            # Transitional compatibility: existing built-in tools can still use
+            # this path, but only after owner, upload-root, and tool-root checks.
             "path": path,
         })
+        manifest.append(ref)
     return manifest
 
 
diff --git a/routes/chat_routes.py b/routes/chat_routes.py
index 705fa4ba96..b8d9934b4c 100644
--- a/routes/chat_routes.py
+++ b/routes/chat_routes.py
@@ -42,7 +42,12 @@
     _enforce_chat_privileges,
 )
 from src.action_intents import ToolIntent, classify_tool_intent as _classify_tool_intent
-from src.tool_policy import build_effective_tool_policy
+from src.tool_policy import (
+    WEB_TOOL_NAMES,
+    build_effective_tool_policy,
+    is_web_search_explicitly_denied,
+    web_search_enabled_for_turn,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -583,10 +588,7 @@ async def chat_stream(request: Request) -> StreamingResponse:
         # below). Skill extraction should only learn from real agent sessions,
         # not chats we quietly promoted for a notes/calendar intent.
         user_requested_agent = (chat_mode == "agent")
-        _search_enabled = (
-            str(allow_web_search).lower() == "true"
-            or str(use_web).lower() == "true"
-        )
+        _search_enabled = web_search_enabled_for_turn(allow_web_search, use_web)
         # Intent auto-escalation: if the user is clearly asking the assistant
         # to create a todo, reminder, or calendar event, promote chat → agent
         # for this turn so the LLM has access to manage_notes / manage_calendar.
@@ -870,23 +872,20 @@ async def chat_stream(request: Request) -> StreamingResponse:
 
         # Build disabled-tools set from frontend toggles + user privileges
         disabled_tools = set()
-        # Only disable bash/web_search when the caller *explicitly* set them
-        # to a falsy value.  When unset (None), defer to per-user privilege
-        # checks below — this lets admins with can_use_bash=True use bash
-        # by default without having to send allow_bash in every request.
+        # Only disable bash when the caller *explicitly* set it to a falsy
+        # value. When unset (None), defer to per-user privilege checks below.
+        # Web search is per-turn opt-in: either the chat pre-search setting
+        # (`use_web=true`) or agent web toggle (`allow_web_search=true`) must
+        # explicitly enable it.
         if allow_bash is not None and str(allow_bash).lower() != "true":
             disabled_tools.add("bash")
-        if (
-            allow_web_search is not None
-            and str(allow_web_search).lower() != "true"
-        ):
-            disabled_tools.add("web_search")
-            disabled_tools.add("web_fetch")
+        _explicit_web_intent = bool(_tool_intent and _tool_intent.category == "web")
+        if is_web_search_explicitly_denied(allow_web_search) or not _search_enabled:
+            disabled_tools.update(WEB_TOOL_NAMES)
         if _explicit_web_intent:
             # A direct lookup/search request should not drift into personal
-            # tools or shell fallbacks. We still keep web_search/web_fetch
-            # available even when the frontend toggle is stale/falsy because
-            # the user's words are the stronger signal.
+            # tools or shell fallbacks. It can only use web_search/web_fetch
+            # when the request's explicit web setting enabled them.
             disabled_tools.update({
                 "bash", "python",
                 "search_chats", "manage_skills", "manage_memory",
@@ -896,11 +895,12 @@ async def chat_stream(request: Request) -> StreamingResponse:
                 "manage_notes", "manage_calendar", "manage_tasks",
                 "api_call", "builtin_browser",
             })
-            disabled_tools.discard("web_search")
-            disabled_tools.discard("web_fetch")
+            if _search_enabled:
+                disabled_tools.difference_update(WEB_TOOL_NAMES)
+            else:
+                disabled_tools.update(WEB_TOOL_NAMES)
         elif _search_enabled:
-            disabled_tools.discard("web_search")
-            disabled_tools.discard("web_fetch")
+            disabled_tools.difference_update(WEB_TOOL_NAMES)
 
         # Nobody/incognito mode: deny tools that would expose the user's
         # persistent memory, past chats, or other identity-linked data.
@@ -951,14 +951,7 @@ async def chat_stream(request: Request) -> StreamingResponse:
         from src.settings import get_setting
         _global_disabled = get_setting("disabled_tools", [])
         if _global_disabled and isinstance(_global_disabled, list):
-            explicit_web_allowed = (
-                _explicit_web_intent
-                or (allow_web_search is not None and str(allow_web_search).lower() == "true")
-            )
-            if explicit_web_allowed:
-                disabled_tools.update(t for t in _global_disabled if t not in {"web_search", "web_fetch"})
-            else:
-                disabled_tools.update(_global_disabled)
+            disabled_tools.update(_global_disabled)
 
         # Light auto-escalation: the user is in chat mode and just expressed a
         # notes/calendar/email intent. Grant the relevant managers but withhold
@@ -1410,10 +1403,8 @@ def _on_research_done(_sid, _result, _sources, _findings):
                     _max_rounds = max(1, min(_max_rounds, 200))
 
                     _forced_tools = None
-                    if _explicit_web_intent:
-                        _forced_tools = {"web_search", "web_fetch"}
-                    elif _search_enabled:
-                        _forced_tools = {"web_search", "web_fetch"}
+                    if _search_enabled:
+                        _forced_tools = set(WEB_TOOL_NAMES)
 
                     async for chunk in stream_agent_loop(
                         sess.endpoint_url,
@@ -1459,7 +1450,9 @@ def _on_research_done(_sid, _result, _sources, _findings):
                                     "tool_start", "tool_output", "agent_step",
                                     "doc_stream_open", "doc_stream_delta",
                                     "doc_update", "doc_suggestions", "ui_control",
-                                    "rounds_exhausted",
+                                    "rounds_exhausted", "budget_exceeded",
+                                    "loop_breaker_triggered",
+                                    "intent_nudge_exhausted",
                                     "ask_user",
                                     "plan_update",
                                 ):
diff --git a/routes/document_routes.py b/routes/document_routes.py
index e1b395e724..dae8b09fa2 100644
--- a/routes/document_routes.py
+++ b/routes/document_routes.py
@@ -12,6 +12,7 @@
 from core.database import Session as DbSession
 from src.auth_helpers import get_current_user, _auth_disabled
 from src.constants import MAIL_ATTACHMENTS_DIR
+from src.upload_handler import reserve_upload_references
 
 logger = logging.getLogger(__name__)
 
@@ -78,6 +79,14 @@ def _email_source_key(content: str) -> tuple[str, str]:
 def setup_document_routes(session_manager, upload_handler=None) -> APIRouter:
     router = APIRouter(tags=["documents"])
 
+    def _reserve_document_uploads(user: Optional[str], content: str) -> None:
+        missing_id = reserve_upload_references(upload_handler, user, content)
+        if missing_id:
+            raise HTTPException(
+                409,
+                f"Referenced upload is no longer available: {missing_id}",
+            )
+
     def _locate_current_user_upload(request: Request, upload_id: str, user: Optional[str]):
         if upload_handler is None:
             return None
@@ -124,6 +133,7 @@ async def create_document(request: Request, req: DocumentCreate) -> Dict[str, An
             if _looks_like_email_document(req.content, req.title):
                 language = "email"
 
+            _reserve_document_uploads(user, req.content)
             _assert_pdf_marker_upload_owned(request, req.content, user, upload_handler)
 
             # Reply drafts are keyed to the source email. If a UI/tool path tries
@@ -636,6 +646,7 @@ async def update_document(request: Request, doc_id: str, req: DocumentUpdate) ->
             if doc.current_content == incoming_content and not req.force_version:
                 return _doc_to_dict(doc)
 
+            _reserve_document_uploads(user, incoming_content)
             _assert_pdf_marker_upload_owned(request, incoming_content, user, upload_handler)
 
             # Check if we can coalesce with the latest version
diff --git a/routes/email_pollers.py b/routes/email_pollers.py
index 13f846a710..8408103daa 100644
--- a/routes/email_pollers.py
+++ b/routes/email_pollers.py
@@ -1068,6 +1068,28 @@ def _scheduled_poll_once() -> dict:
         for r in rows:
             sid = r[0]
             try:
+                # Atomically claim this row before doing any work. Two
+                # pollers can race here (the in-process asyncio task and an
+                # externally cron-driven `odysseus-mail poll-scheduled`, or
+                # an admin running the CLI manually alongside the in-process
+                # one despite the ODYSSEUS_INPROCESS_POLLERS=0 guidance) -
+                # both can SELECT the same 'pending' row before either has
+                # updated its status. The UPDATE...WHERE status='pending' is
+                # the atomicity boundary: only the poller whose UPDATE
+                # actually changes a row (rowcount == 1) proceeds to send;
+                # a loser sees rowcount == 0 and skips it instead of sending
+                # a duplicate.
+                claim_conn = sqlite3.connect(SCHEDULED_DB)
+                claim_cur = claim_conn.execute(
+                    "UPDATE scheduled_emails SET status='sending' WHERE id=? AND status='pending'",
+                    (sid,),
+                )
+                claim_conn.commit()
+                claimed = claim_cur.rowcount == 1
+                claim_conn.close()
+                if not claimed:
+                    continue
+
                 attachments = json.loads(r[8] or "[]")
                 row_account_id = r[9] if len(r) > 9 else None
                 odysseus_kind = r[10] if len(r) > 10 else "scheduled"
diff --git a/routes/email_routes.py b/routes/email_routes.py
index 9bbf7eda0b..fba679cc18 100644
--- a/routes/email_routes.py
+++ b/routes/email_routes.py
@@ -923,29 +923,32 @@ def _resolve_send_config(account_id: str | None = None, owner: str = "") -> dict
 
 
 def _store_email_flag(conn, uid: str, flag: str, add: bool = True) -> bool:
+    # imaplib's plain store() takes a message SEQUENCE NUMBER, not a UID, so the
+    # old `else` fallback flagged whichever message happened to occupy sequence
+    # position == the UID value. When the UID isn't present, fail safe (callers
+    # surface "Email not found") rather than touch an unrelated message.
+    if not _uid_exists(conn, uid):
+        return False
     op = "+FLAGS" if add else "-FLAGS"
-    if _uid_exists(conn, uid):
-        status, _ = conn.uid("STORE", _uid_bytes(uid), op, flag)
-    else:
-        status, _ = conn.store(_uid_bytes(uid), op, flag)
+    status, _ = conn.uid("STORE", _uid_bytes(uid), op, flag)
     return status == "OK"
 
 
 def _move_email_message(conn, uid: str, dest: str, role: str = "") -> bool:
     dest = _resolve_mail_folder(conn, dest, role or _folder_role_from_name(dest))
-    if _uid_exists(conn, uid):
-        status, _ = conn.uid("MOVE", _uid_bytes(uid), _q(dest))
-        if status == "OK":
-            return True
-        status, _ = conn.uid("COPY", _uid_bytes(uid), _q(dest))
-        if status != "OK":
-            return False
-        status, _ = conn.uid("STORE", _uid_bytes(uid), "+FLAGS", "\\Deleted")
-    else:
-        status, _ = conn.copy(_uid_bytes(uid), _q(dest))
-        if status != "OK":
-            return False
-        status, _ = conn.store(_uid_bytes(uid), "+FLAGS", "\\Deleted")
+    # copy()/store() are SEQUENCE-NUMBER commands; using them with a UID (the old
+    # `else` branch) copied + \Deleted-flagged the wrong message and then
+    # expunge() permanently removed it. There is no valid case where treating a
+    # UID as a sequence number is correct, so fail safe when the UID is absent.
+    if not _uid_exists(conn, uid):
+        return False
+    status, _ = conn.uid("MOVE", _uid_bytes(uid), _q(dest))
+    if status == "OK":
+        return True
+    status, _ = conn.uid("COPY", _uid_bytes(uid), _q(dest))
+    if status != "OK":
+        return False
+    status, _ = conn.uid("STORE", _uid_bytes(uid), "+FLAGS", "\\Deleted")
     if status == "OK":
         conn.expunge()
         return True
diff --git a/routes/history/history_routes.py b/routes/history/history_routes.py
index 2324ae286a..d0d45e8eb2 100644
--- a/routes/history/history_routes.py
+++ b/routes/history/history_routes.py
@@ -10,7 +10,9 @@
 
 from core.models import ChatMessage
 from core.database import SessionLocal, ChatMessage as DbChatMessage, Session as DbSession
+from src.auth_helpers import effective_user
 from src.topic_analyzer import analyze_topics
+from src.upload_handler import reserve_message_upload_references
 from routes.session_routes import (
     _message_role,
     _message_text,
@@ -98,9 +100,29 @@ def _merge_continue_rows_to_delete(db_messages, db1, db2):
     return to_delete
 
 
-def setup_history_routes(session_manager) -> APIRouter:
+def setup_history_routes(session_manager, upload_handler=None) -> APIRouter:
     router = APIRouter(tags=["history"])
 
+    def _reserve_message_uploads(
+        request: Request,
+        content: Any,
+        metadata: Any = None,
+    ) -> None:
+        try:
+            missing_id = reserve_message_upload_references(
+                upload_handler,
+                effective_user(request),
+                content,
+                metadata,
+            )
+        except (TypeError, ValueError) as exc:
+            raise HTTPException(400, "Invalid message attachment metadata") from exc
+        if missing_id:
+            raise HTTPException(
+                409,
+                f"Referenced upload is no longer available: {missing_id}",
+            )
+
     def _db_history_entry(m: DbChatMessage) -> Dict[str, Any]:
         entry = {"role": m.role, "content": _history_display_content(m.content)}
         meta = {}
@@ -251,7 +273,9 @@ async def add_message(request: Request, session_id: str):
             content = body.get("content", "")
             if not content:
                 raise HTTPException(400, "content is required")
-            msg = ChatMessage(role=role, content=content, metadata=body.get("metadata"))
+            metadata = body.get("metadata")
+            _reserve_message_uploads(request, content, metadata)
+            msg = ChatMessage(role=role, content=content, metadata=metadata)
             session_manager.add_message(session_id, msg)
             return {"status": "ok"}
         except KeyError:
@@ -331,6 +355,8 @@ async def edit_message(request: Request, session_id: str):
             if not msg_id or content is None:
                 raise HTTPException(400, "msg_id and content are required")
 
+            _reserve_message_uploads(request, content)
+
             session = session_manager.get_session(session_id)
             db = SessionLocal()
             try:
diff --git a/routes/note_routes.py b/routes/note_routes.py
index 3d356f5c99..ec45072646 100644
--- a/routes/note_routes.py
+++ b/routes/note_routes.py
@@ -13,6 +13,7 @@
 from core.middleware import INTERNAL_TOOL_USER
 from src.auth_helpers import require_user
 from src.constants import DATA_DIR
+from src.upload_handler import reserve_upload_references
 from sqlalchemy.orm.attributes import flag_modified
 
 logger = logging.getLogger(__name__)
@@ -479,7 +480,9 @@ def _smtp_send():
                 base = intg["base_url"].rstrip("/")
                 topic = settings.get("reminder_ntfy_topic") or "reminders"
                 ntfy_body = synthesis or note_body or title
-                hdrs = {"Title": title or "Reminder", "Priority": "high", "Tags": "bell"}
+                # ntfy Title is an ASCII HTTP header; sanitize Unicode and cap its length.
+                _clean_title = (title or "Reminder").encode("ascii", "replace").decode("ascii")[:200]
+                hdrs = {"Title": _clean_title, "Priority": "high", "Tags": "bell"}
                 api_key = intg.get("api_key", "")
                 if api_key:
                     hdrs["Authorization"] = f"Bearer {api_key}"
@@ -572,7 +575,7 @@ def _smtp_send():
 # Router factory
 # ---------------------------------------------------------------------------
 
-def setup_note_routes(task_scheduler=None):
+def setup_note_routes(task_scheduler=None, upload_handler=None):
     # Expose the scheduler to module-level `dispatch_reminder` so reminders
     # can also push to the in-app notification queue (the polling system
     # turns each entry into a real browser Notification + the existing
@@ -594,6 +597,11 @@ def _owner(request: Request) -> Optional[str]:
         # did not.
         return require_user(request) or None
 
+    def _reserve_note_uploads(owner: Optional[str], *values) -> None:
+        missing_id = reserve_upload_references(upload_handler, owner, *values)
+        if missing_id:
+            raise HTTPException(409, f"Referenced upload is no longer available: {missing_id}")
+
     def _is_admin_or_single_user(request: Request, user: str | None) -> bool:
         if user == INTERNAL_TOOL_USER:
             return True
@@ -643,6 +651,13 @@ def list_notes(
     @router.post("")
     def create_note(request: Request, body: NoteCreate):
         user = _owner(request)
+        _reserve_note_uploads(
+            user,
+            body.image_url,
+            body.color,
+            body.content,
+            json.dumps(body.items) if body.items is not None else None,
+        )
         db = SessionLocal()
         try:
             note = Note(
@@ -700,6 +715,13 @@ def update_note(request: Request, note_id: str, body: NoteUpdate):
             if user is not None and note.owner != user:
                 raise HTTPException(404, "Note not found")
 
+            _reserve_note_uploads(
+                user,
+                body.image_url,
+                body.color,
+                body.content,
+                json.dumps(body.items) if body.items is not None else None,
+            )
             if body.title is not None:
                 note.title = body.title
             if body.content is not None:
diff --git a/routes/session_routes.py b/routes/session_routes.py
index 2d3543e369..2d8a6d87f3 100644
--- a/routes/session_routes.py
+++ b/routes/session_routes.py
@@ -13,6 +13,7 @@
 from core.database import Session as DbSession, SessionLocal, Document, GalleryImage, utcnow_naive
 from src.auth_helpers import effective_user, _auth_disabled, owner_filter
 from src.session_actions import is_session_recently_active
+from src.upload_handler import reserve_message_upload_references
 
 
 def _sanitize_export_filename(name: str) -> str:
@@ -203,7 +204,12 @@ def _pick_endpoint_for_sort(owner=None):
         return url, model, headers
     return None, None, None
 
-def setup_session_routes(session_manager: SessionManager, config: dict, webhook_manager=None):
+def setup_session_routes(
+    session_manager: SessionManager,
+    config: dict,
+    webhook_manager=None,
+    upload_handler=None,
+):
     """Setup session routes with the provided manager and config"""
 
     REQUEST_TIMEOUT = config.get("REQUEST_TIMEOUT", 20)
@@ -537,6 +543,22 @@ async def inject_messages(request: Request, sid: str):
         body = await request.json()
         messages = body.get("messages", [])
         from core.models import ChatMessage
+        owner = effective_user(request)
+        try:
+            for message in messages:
+                missing_id = reserve_message_upload_references(
+                    upload_handler,
+                    owner,
+                    message.get("content"),
+                    message.get("metadata"),
+                )
+                if missing_id:
+                    raise HTTPException(
+                        409,
+                        f"Referenced upload is no longer available: {missing_id}",
+                    )
+        except (AttributeError, TypeError, ValueError) as exc:
+            raise HTTPException(400, "Invalid message attachment metadata") from exc
         for m in messages:
             sess.add_message(ChatMessage(m["role"], m["content"], metadata=m.get("metadata")))
         session_manager.save_sessions()
diff --git a/routes/upload_routes.py b/routes/upload_routes.py
index 1bd402ac8a..fb702e45a7 100644
--- a/routes/upload_routes.py
+++ b/routes/upload_routes.py
@@ -10,16 +10,140 @@
 from typing import List, Optional
 import logging
 from core.middleware import require_admin
-from core.database import SessionLocal, GalleryImage, Session as DbSession
+from core.database import (
+    SessionLocal,
+    ChatMessage as DbChatMessage,
+    CalendarCal,
+    CalendarEvent,
+    Document,
+    DocumentVersion,
+    GalleryImage,
+    Note,
+    Session as DbSession,
+)
 from src.auth_helpers import effective_user
+from src.attachment_refs import attachment_refs_from_metadata
 from src.constants import GENERATED_IMAGES_DIR
-from src.upload_handler import count_recent_uploads
+from src.upload_handler import (
+    UploadCleanupSafetyError,
+    count_recent_uploads,
+    extract_upload_ids,
+)
 
 logger = logging.getLogger(__name__)
 
 router = APIRouter(prefix="/api/upload", tags=["upload"])
 UPLOAD_RESPONSE_HEADERS = {"X-Content-Type-Options": "nosniff"}
 
+def _upload_ids_from_persisted_text(value: object) -> set[str]:
+    """Return canonical upload IDs embedded in persisted text.
+
+    This covers attachment reference lines/URIs and the PDF source markers
+    stored by the document editor. False positives are intentionally
+    conservative: retaining an extra upload is safer than deleting referenced
+    bytes.
+    """
+    return extract_upload_ids(value)
+
+
+def _upload_ids_from_message_metadata(raw_metadata: object) -> set[str]:
+    """Extract attachment IDs from a persisted chat metadata JSON value.
+
+    Malformed metadata raises instead of being treated as an empty reference
+    set. The admin cleanup route catches that failure and aborts cleanup.
+    """
+    if raw_metadata in (None, ""):
+        return set()
+    if isinstance(raw_metadata, str):
+        metadata = json.loads(raw_metadata)
+    else:
+        metadata = raw_metadata
+    if not isinstance(metadata, dict):
+        raise ValueError("chat message metadata must be a JSON object")
+
+    attachments = metadata.get("attachments")
+    if attachments is not None:
+        if not isinstance(attachments, list) or any(
+            not isinstance(item, dict) for item in attachments
+        ):
+            raise ValueError("chat message attachments metadata is malformed")
+
+    ids = {
+        str(ref["attachment_id"])
+        for ref in attachment_refs_from_metadata(metadata)
+        if ref.get("attachment_id")
+    }
+    # Preserve canonical IDs even in older metadata shapes not normalized by
+    # attachment_refs_from_metadata().
+    ids.update(_upload_ids_from_persisted_text(json.dumps(metadata)))
+    return ids
+
+
+def _collect_persisted_upload_references() -> tuple[set[str], set[str]]:
+    """Collect upload IDs/hashes still referenced by durable application data.
+
+    The caller must treat any exception as an incomplete scan and fail closed.
+    There is no distinct artifact table in the current schema; artifact-like
+    attachment references persisted in chat/document text are covered by the
+    canonical-ID scan.
+    """
+    referenced_ids: set[str] = set()
+    referenced_hashes: set[str] = set()
+    db = SessionLocal()
+    try:
+        for content, raw_metadata in db.query(
+            DbChatMessage.content,
+            DbChatMessage.meta_data,
+        ).yield_per(500):
+            referenced_ids.update(_upload_ids_from_persisted_text(content))
+            referenced_ids.update(_upload_ids_from_message_metadata(raw_metadata))
+
+        for (content,) in db.query(Document.current_content).yield_per(500):
+            referenced_ids.update(_upload_ids_from_persisted_text(content))
+
+        for (content,) in db.query(DocumentVersion.content).yield_per(500):
+            referenced_ids.update(_upload_ids_from_persisted_text(content))
+
+        for filename, file_hash in db.query(
+            GalleryImage.filename,
+            GalleryImage.file_hash,
+        ).yield_per(500):
+            referenced_ids.update(_upload_ids_from_persisted_text(filename))
+            if file_hash:
+                referenced_hashes.add(str(file_hash))
+
+        for image_url, color, content, items in db.query(
+            Note.image_url,
+            Note.color,
+            Note.content,
+            Note.items,
+        ).yield_per(500):
+            for value in (image_url, color, content, items):
+                referenced_ids.update(_upload_ids_from_persisted_text(value))
+
+        for (color,) in db.query(CalendarCal.color).yield_per(500):
+            referenced_ids.update(_upload_ids_from_persisted_text(color))
+
+        for color, description, location in db.query(
+            CalendarEvent.color,
+            CalendarEvent.description,
+            CalendarEvent.location,
+        ).yield_per(500):
+            for value in (color, description, location):
+                referenced_ids.update(_upload_ids_from_persisted_text(value))
+
+        return referenced_ids, referenced_hashes
+    finally:
+        db.close()
+
+
+def _run_reference_safe_cleanup(upload_handler) -> int:
+    referenced_ids, referenced_hashes = _collect_persisted_upload_references()
+    return upload_handler.cleanup_old_uploads(
+        referenced_upload_ids=referenced_ids,
+        referenced_upload_hashes=referenced_hashes,
+    )
+
 def setup_upload_routes(upload_handler):
     """Setup upload routes with the provided handler"""
 
@@ -172,7 +296,9 @@ async def api_upload(
                     "mime": meta["mime"],
                     "size": meta["size"],
                     "hash": meta["hash"],
+                    "checksum_sha256": meta.get("checksum_sha256") or meta["hash"],
                     "uploaded_at": meta["uploaded_at"],
+                    "created_at": meta.get("created_at") or meta["uploaded_at"],
                     "width": meta.get("width"),
                     "height": meta.get("height"),
                     "is_duplicate": meta.get("is_duplicate", False)
@@ -195,7 +321,23 @@ async def api_upload(
     async def manual_cleanup(request: Request):
         """Manually trigger cleanup of old uploads."""
         require_admin(request)
-        cleaned_count = upload_handler.cleanup_old_uploads()
+        try:
+            cleaned_count = await asyncio.to_thread(
+                _run_reference_safe_cleanup,
+                upload_handler,
+            )
+        except UploadCleanupSafetyError:
+            logger.exception("Upload cleanup aborted because index safety checks failed")
+            raise HTTPException(
+                503,
+                "Upload cleanup aborted because upload index integrity could not be verified",
+            )
+        except Exception:
+            logger.exception("Upload cleanup skipped because reference discovery failed")
+            raise HTTPException(
+                503,
+                "Upload cleanup skipped because persisted references could not be verified",
+            )
         return {"status": "success", "files_cleaned": cleaned_count}
 
     @router.get("/stats")
diff --git a/scripts/odysseus-backup b/scripts/odysseus-backup
index b0f3120746..9709ed6b53 100755
--- a/scripts/odysseus-backup
+++ b/scripts/odysseus-backup
@@ -133,18 +133,32 @@ def cmd_list(args):
         emit([], args)
         return
     entries = []
-    for p in sorted(_BACKUP_DIR.iterdir(), key=lambda x: x.stat().st_mtime, reverse=True):
-        if not p.is_file():
-            continue
-        entries.append({
-            "path": str(p),
-            "name": p.name,
-            "bytes": p.stat().st_size,
-            "modified": datetime.fromtimestamp(p.stat().st_mtime).isoformat(),
-        })
+    for p in _BACKUP_DIR.iterdir():
+        entry = _backup_entry(p)
+        if entry is not None:
+            entries.append(entry)
+    entries.sort(key=lambda entry: entry["_mtime"], reverse=True)
+    for entry in entries:
+        entry.pop("_mtime", None)
     emit(entries, args)
 
 
+def _backup_entry(p):
+    try:
+        if not p.is_file():
+            return None
+        st = p.stat()
+    except OSError:
+        return None
+    return {
+        "path": str(p),
+        "name": p.name,
+        "bytes": st.st_size,
+        "modified": datetime.fromtimestamp(st.st_mtime).isoformat(),
+        "_mtime": st.st_mtime,
+    }
+
+
 def cmd_verify(args):
     """Open the tarball read-only and walk its members — confirms
     integrity without extracting anything."""
diff --git a/scripts/odysseus-memory b/scripts/odysseus-memory
index 1a4f8a0337..04ef67894f 100755
--- a/scripts/odysseus-memory
+++ b/scripts/odysseus-memory
@@ -90,7 +90,7 @@ def cmd_add(args):
     # add_entry doesn't save by default — the call in chat does it
     # after dedup checks. Persist here so a one-shot CLI add sticks.
     all_entries = _manager().load_all()
-    if not any(e.get("id") == entry.get("id") for e in all_entries):
+    if not any(isinstance(e, dict) and e.get("id") == entry.get("id") for e in all_entries):
         all_entries.append(entry)
         _manager().save(all_entries)
     emit(entry, args)
diff --git a/services/hwfit/models.py b/services/hwfit/models.py
index 6f2bb00e7a..c042c9462a 100644
--- a/services/hwfit/models.py
+++ b/services/hwfit/models.py
@@ -145,7 +145,7 @@ def is_prequantized(model):
         or re.search(r"(^|[-_/])fp8($|[-_/\s])", text) is not None
         or (not (model.get("is_gguf") or model.get("gguf_sources")) and re.search(r"(^|[-_/])(?:int)?8bit($|[-_/\s])", text) is not None)
         or any(x in text for x in ("awq", "gptq", "mlx"))
-        or any(q.startswith(p) for p in PREQUANTIZED_PREFIXES)
+        or any(isinstance(q, str) and q.startswith(p) for p in PREQUANTIZED_PREFIXES)
     )
 
 
@@ -155,7 +155,7 @@ def params_b(model):
         return raw / 1_000_000_000.0
 
     pc = model.get("parameter_count", "")
-    if pc:
+    if isinstance(pc, str) and pc:
         pc = pc.strip().upper()
         m = re.match(r"^([\d.]+)\s*([BKMGT]?)$", pc)
         if m:
diff --git a/services/memory/skill_importer.py b/services/memory/skill_importer.py
index 65f4b21c0a..2f0d7ab326 100644
--- a/services/memory/skill_importer.py
+++ b/services/memory/skill_importer.py
@@ -6,7 +6,7 @@
 import re
 from dataclasses import dataclass
 from typing import Dict, List, Optional, Tuple
-from urllib.parse import quote, urlparse
+from urllib.parse import quote, urljoin, urlparse
 
 import httpx
 
@@ -68,6 +68,52 @@ def _is_text_file(name: str) -> bool:
     return any(low.endswith(s) for s in ALLOWED_SUFFIXES)
 
 
+# Max redirect hops to follow manually while re-validating each one.
+_MAX_FETCH_REDIRECTS = 5
+
+
+def _check_fetch_url(url: str) -> None:
+    """SSRF guard for skill-import fetches (defense-in-depth).
+
+    Skill bundles only ever come from public GitHub, never an internal
+    address, so block private/loopback/link-local targets on every hop —
+    matching the hardened web-fetch path in
+    ``services/search/content.py:_get_public_url`` rather than the lenient
+    default used for admin-configured model endpoints.
+    """
+    ok, reason = check_outbound_url(url, block_private=True)
+    if not ok:
+        raise SkillImportError(reason)
+
+
+def _get_checked(
+    url: str,
+    *,
+    headers: Optional[dict] = None,
+    timeout: float = 30.0,
+) -> httpx.Response:
+    """GET that follows redirects manually, re-running the SSRF guard per hop.
+
+    ``httpx``'s ``follow_redirects=True`` validates only the initial URL, so a
+    ``3xx`` to an internal address (``169.254.169.254``, ``127.0.0.1``, …) would
+    still be connected to before any post-hoc host check. Following redirects by
+    hand lets us re-validate every hop, closing that blind-SSRF gap.
+    """
+    current = url
+    with httpx.Client(follow_redirects=False, timeout=timeout) as client:
+        for _ in range(_MAX_FETCH_REDIRECTS + 1):
+            _check_fetch_url(current)
+            r = client.get(current, headers=headers)
+            if r.status_code in (301, 302, 303, 307, 308):
+                location = r.headers.get("location")
+                if not location:
+                    return r
+                current = urljoin(str(r.url), location)
+                continue
+            return r
+    raise SkillImportError("too many redirects while fetching skill bundle")
+
+
 def parse_skill_source(url: str) -> ResolvedSource:
     """Normalize skills.sh / GitHub web URLs into owner/repo/ref/path."""
     raw = (url or "").strip()
@@ -76,22 +122,18 @@ def parse_skill_source(url: str) -> ResolvedSource:
 
     # skills.sh often links to GitHub; try to unwrap ?url= or redirect target later.
     if "skills.sh" in raw and "github.com" not in raw:
-        ok, reason = check_outbound_url(raw)
-        if not ok:
-            raise SkillImportError(reason)
-        with httpx.Client(follow_redirects=True, timeout=20.0) as client:
-            r = client.get(raw)
-            if r.status_code >= 400:
-                raise _github_response_error(r)
-            final = str(r.url)
-            _assert_github_url(final, context="redirect target")
-            # Page may embed a github link; prefer final URL if redirected.
-            if "github.com" in final:
-                raw = final
-            else:
-                m = re.search(r"https?://github\.com/[^\s\"')]+", r.text or "")
-                if m:
-                    raw = m.group(0).rstrip(".,)")
+        r = _get_checked(raw, timeout=20.0)
+        if r.status_code >= 400:
+            raise _github_response_error(r)
+        final = str(r.url)
+        _assert_github_url(final, context="redirect target")
+        # Page may embed a github link; prefer final URL if redirected.
+        if "github.com" in final:
+            raw = final
+        else:
+            m = re.search(r"https?://github\.com/[^\s\"')]+", r.text or "")
+            if m:
+                raw = m.group(0).rstrip(".,)")
 
     parsed = urlparse(raw)
     host = _github_host(raw)
@@ -165,17 +207,13 @@ def _github_response_error(response: httpx.Response) -> SkillImportError:
 
 
 def _fetch_bytes(url: str) -> bytes:
-    ok, reason = check_outbound_url(url)
-    if not ok:
-        raise SkillImportError(reason)
-    with httpx.Client(follow_redirects=True, timeout=30.0) as client:
-        r = client.get(url, headers={"Accept": "application/vnd.github+json"})
-        if r.status_code >= 400:
-            raise _github_response_error(r)
-        _assert_github_url(str(r.url), context="redirect target")
-        if len(r.content) > MAX_FILE_BYTES:
-            raise SkillImportError(f"file too large: {url}")
-        return r.content
+    r = _get_checked(url, headers={"Accept": "application/vnd.github+json"}, timeout=30.0)
+    if r.status_code >= 400:
+        raise _github_response_error(r)
+    _assert_github_url(str(r.url), context="redirect target")
+    if len(r.content) > MAX_FILE_BYTES:
+        raise SkillImportError(f"file too large: {url}")
+    return r.content
 
 
 def _fetch_text(url: str) -> str:
@@ -190,15 +228,11 @@ def _list_github_dir(src: ResolvedSource, rel_dir: str, out: Dict[str, str], *,
     if depth > 4 or len(out) >= MAX_FILES:
         return
     url = _api_contents_url(src, rel_dir)
-    ok, reason = check_outbound_url(url)
-    if not ok:
-        raise SkillImportError(reason)
-    with httpx.Client(follow_redirects=True, timeout=30.0) as client:
-        r = client.get(url, headers={"Accept": "application/vnd.github+json"})
-        if r.status_code >= 400:
-            raise _github_response_error(r)
-        _assert_github_url(str(r.url), context="redirect target")
-        entries = r.json()
+    r = _get_checked(url, headers={"Accept": "application/vnd.github+json"}, timeout=30.0)
+    if r.status_code >= 400:
+        raise _github_response_error(r)
+    _assert_github_url(str(r.url), context="redirect target")
+    entries = r.json()
     if not isinstance(entries, list):
         raise SkillImportError("expected a directory on GitHub")
     total = sum(len(v.encode("utf-8")) for v in out.values())
diff --git a/services/tts/tts_service.py b/services/tts/tts_service.py
index e724434cb6..2120d7720f 100644
--- a/services/tts/tts_service.py
+++ b/services/tts/tts_service.py
@@ -68,7 +68,7 @@ def available(self) -> bool:
         if provider == "local":
             kokoro = self._get_kokoro()
             return kokoro is not None and kokoro.available
-        if provider.startswith("endpoint:"):
+        if isinstance(provider, str) and provider.startswith("endpoint:"):
             return True  # assume reachable; errors surface at synthesis time
         return False
 
diff --git a/src/agent_loop.py b/src/agent_loop.py
index ebc2a99a62..6f7dde6054 100644
--- a/src/agent_loop.py
+++ b/src/agent_loop.py
@@ -24,7 +24,7 @@
 from src.settings import get_setting
 from src.prompt_security import untrusted_context_message
 from src.tool_security import blocked_tools_for_owner, plan_mode_disabled_tools
-from src.tool_policy import GUIDE_ONLY_DIRECTIVE, ToolPolicy
+from src.tool_policy import GUIDE_ONLY_DIRECTIVE, WEB_TOOL_NAMES, ToolPolicy
 from src.tool_utils import _truncate, get_mcp_manager
 from src.agent_tools import (
     parse_tool_blocks,
@@ -321,7 +321,7 @@ def _load_mcp_disabled_map() -> Dict[str, set]:
 }
 
 _DOMAIN_TOOL_MAP = {
-    "web": {"web_search", "web_fetch"},
+    "web": set(WEB_TOOL_NAMES),
     "documents": {"create_document", "edit_document", "update_document", "suggest_document", "manage_documents"},
     "email": {"list_email_accounts", "list_emails", "read_email", "send_email", "reply_to_email", "bulk_email", "archive_email", "delete_email", "mark_email_read", "resolve_contact", "manage_contact"},
     "cookbook": {"download_model", "serve_model", "serve_preset", "list_serve_presets", "list_served_models", "stop_served_model", "tail_serve_output", "list_downloads", "cancel_download", "search_hf_models", "list_cached_models", "list_cookbook_servers", "adopt_served_model"},
@@ -2847,13 +2847,12 @@ async def stream_agent_loop(
         if "email" in (_intent.get("domains") or set()):
             _relevant_tools.add("ui_control")
         if "web" in (_intent.get("domains") or set()):
-            _relevant_tools.update({"web_search", "web_fetch"})
-            _removed_web_blocks = sorted({"web_search", "web_fetch"} & disabled_tools)
-            if _removed_web_blocks:
-                disabled_tools.difference_update({"web_search", "web_fetch"})
+            _relevant_tools.update(WEB_TOOL_NAMES)
+            _blocked_web_tools = sorted(WEB_TOOL_NAMES & disabled_tools)
+            if _blocked_web_tools:
                 logger.info(
-                    "[agent-intent] web turn forced search tools enabled; removed disabled=%s",
-                    _removed_web_blocks,
+                    "[agent-intent] web domain selected but search tools remain disabled=%s",
+                    _blocked_web_tools,
                 )
         if "ui" in (_intent.get("domains") or set()):
             _relevant_tools.add("ui_control")
@@ -2887,9 +2886,9 @@ async def stream_agent_loop(
             _relevant_tools = set(ALWAYS_AVAILABLE)
         _relevant_tools.update({"read_file", "grep", "ls", "manage_documents"})
 
-    # Per-request forced tools are stronger than retrieval. Search toggles and
-    # explicit lookup turns must make web tools visible even when tool RAG
-    # misses them; route-level disabled_tools decides what else is allowed.
+    # Per-request forced tools are stronger than retrieval. Explicit search
+    # settings make web tools visible even when tool RAG misses them;
+    # route-level disabled_tools decides what remains allowed.
     if not guide_only and forced_tools:
         forced_set = {t for t in forced_tools if t not in disabled_tools}
         if _relevant_tools is None:
@@ -3829,9 +3828,8 @@ async def stream_agent_loop(
                 and _intent_match is not None
                 and len(_intent_text) < 400
                 and "```" not in _intent_text
-                and _intent_nudge_count < _MAX_INTENT_NUDGES
             )
-            if _looks_like_promise:
+            if _looks_like_promise and _intent_nudge_count < _MAX_INTENT_NUDGES:
                 _intent_nudge_count += 1
                 _matched_phrase = _intent_match.group(0).strip()
                 logger.info(f"[agent] intent-without-action nudge #{_intent_nudge_count} on round {round_num}: {_matched_phrase!r}")
@@ -3860,6 +3858,31 @@ async def stream_agent_loop(
                 # Visible signal in the stream so the user knows we caught it.
                 yield f'data: {json.dumps({"type": "agent_step", "round": round_num + 1})}\n\n'
                 continue
+            if _looks_like_promise:
+                _matched_phrase = _intent_match.group(0).strip()
+                _guard_message = (
+                    "The agent stopped because it repeatedly announced a tool "
+                    "action without making the tool call."
+                )
+                logger.warning(
+                    "[agent] intent-without-action guard exhausted on round %d after %d nudges: %r",
+                    round_num,
+                    _intent_nudge_count,
+                    _matched_phrase,
+                )
+                yield (
+                    "data: "
+                    + json.dumps({
+                        "type": "intent_nudge_exhausted",
+                        "reason": "intent_without_action_nudge_cap",
+                        "message": _guard_message,
+                        "round": round_num,
+                        "nudges": _intent_nudge_count,
+                        "matched": _matched_phrase,
+                    })
+                    + "\n\n"
+                )
+                break
             break  # no tools — done
 
         # ── Loop-breaker (Terminus-style stall detector) ──────────────
@@ -3896,6 +3919,21 @@ async def stream_agent_loop(
             reason = (f"calling {_runaway} with identical arguments over and over" if _runaway
                       else "repeating the same tool calls without new progress")
             logger.warning(f"[agent] loop-breaker tripped on round {round_num} ({reason}); sig={_sig[:80]!r}")
+            yield (
+                "data: "
+                    + json.dumps({
+                    "type": "loop_breaker_triggered",
+                    "reason": "loop_breaker_stall",
+                    "message": (
+                        "The loop-breaker detected repeated tool calls without "
+                        "new progress, so the agent is being forced to stop "
+                        "using tools and give its best final answer."
+                    ),
+                    "round": round_num,
+                    "detail": reason,
+                })
+                + "\n\n"
+            )
             # The model has been executing tools, so its results are already
             # in context. Force ONE tool-free round to converge: write the
             # answer from what it has, or state plainly what's blocking it.
@@ -4014,16 +4052,31 @@ async def _run_tool():
                         await _progress_q.put(None)
 
                 _tool_task = asyncio.create_task(_run_tool())
-                # Drain progress events as they arrive — block until the
-                # next event OR the tool finishes (sentinel = None).
-                while True:
-                    evt = await _progress_q.get()
-                    if evt is None:
-                        break
-                    yield (
-                        f'data: {json.dumps({"type": "tool_progress", "tool": block.tool_type, "round": round_num, **evt})}\n\n'
-                    )
-                desc, result = await _tool_task
+                try:
+                    # Drain progress events as they arrive — block until the
+                    # next event OR the tool finishes (sentinel = None).
+                    while True:
+                        evt = await _progress_q.get()
+                        if evt is None:
+                            break
+                        yield (
+                            f'data: {json.dumps({"type": "tool_progress", "tool": block.tool_type, "round": round_num, **evt})}\n\n'
+                        )
+                    desc, result = await _tool_task
+                finally:
+                    # If the SSE client disconnects (or this generator is
+                    # otherwise closed) while we're awaiting a progress event
+                    # above, GeneratorExit is thrown in right here and the
+                    # `await _tool_task` on the line above never runs — the
+                    # task (and any subprocess execute_tool_block spawned for
+                    # bash/python tools) would otherwise keep running
+                    # orphaned with nothing left to await or cancel it.
+                    if not _tool_task.done():
+                        _tool_task.cancel()
+                        try:
+                            await _tool_task
+                        except (asyncio.CancelledError, Exception):
+                            pass
 
             # A skill the model just loaded can prescribe tools that weren't
             # RAG-selected this turn (declared via requires_toolsets in its
diff --git a/src/agent_tools/document_tools.py b/src/agent_tools/document_tools.py
index 2ab8659d30..65ee0461ec 100644
--- a/src/agent_tools/document_tools.py
+++ b/src/agent_tools/document_tools.py
@@ -2,10 +2,16 @@
 import logging
 import re
 from src.constants import MAX_READ_CHARS
-from src.tool_utils import _parse_tool_args
+from src.tool_utils import _parse_tool_args, get_upload_handler
+from src.upload_handler import reserve_upload_references
 
 logger = logging.getLogger(__name__)
 
+
+def _missing_document_upload(owner: Optional[str], content: Any) -> Optional[str]:
+    """Reserve explicit upload URLs before an agent persists document text."""
+    return reserve_upload_references(get_upload_handler(), owner, content)
+
 # ---------------------------------------------------------------------------
 # Active document state
 # ---------------------------------------------------------------------------
@@ -384,6 +390,13 @@ async def execute(self, content: str, ctx: dict) -> dict:
                 return {"error": "Cannot create document in another user's session"}
             _owner = _sess.owner if _sess else None
 
+            missing_id = _missing_document_upload(_owner, content)
+            if missing_id:
+                return {
+                    "error": f"Referenced upload is no longer available: {missing_id}",
+                    "exit_code": 1,
+                }
+
             doc = Document(
                 id=doc_id,
                 session_id=session_id,
@@ -455,6 +468,13 @@ async def execute(self, content: str, ctx: dict) -> Dict:
             if is_email_doc:
                 doc.language = "email"
 
+            missing_id = _missing_document_upload(owner, new_content)
+            if missing_id:
+                return {
+                    "error": f"Referenced upload is no longer available: {missing_id}",
+                    "exit_code": 1,
+                }
+
             if not is_email_doc and _pdf_source_upload_id(doc.current_content or ""):
                 return _create_pdf_text_derivative(
                     db,
@@ -532,6 +552,12 @@ async def execute(self, content: str, ctx: dict) -> Dict:
                     applied = 1
                     skipped = max(0, len(edits) - 1)
                     doc.language = "email"
+                    missing_id = _missing_document_upload(owner, updated_content)
+                    if missing_id:
+                        return {
+                            "error": f"Referenced upload is no longer available: {missing_id}",
+                            "exit_code": 1,
+                        }
                     new_ver = doc.version_count + 1
                     ver = DocumentVersion(
                         id=str(uuid.uuid4()),
@@ -584,6 +610,13 @@ async def execute(self, content: str, ctx: dict) -> Dict:
             if applied == 0:
                 return {"error": f"No edits applied — none of the FIND blocks matched the document content (skipped {skipped})"}
 
+            missing_id = _missing_document_upload(owner, updated_content)
+            if missing_id:
+                return {
+                    "error": f"Referenced upload is no longer available: {missing_id}",
+                    "exit_code": 1,
+                }
+
             if _pdf_source_upload_id(doc.current_content or ""):
                 return _create_pdf_text_derivative(
                     db,
diff --git a/src/app_initializer.py b/src/app_initializer.py
index b438b2b173..1b29f06d26 100644
--- a/src/app_initializer.py
+++ b/src/app_initializer.py
@@ -21,6 +21,7 @@
 from src.chat_handler import ChatHandler
 from src.research_handler import ResearchHandler
 from src.upload_handler import UploadHandler
+from src.tool_utils import set_upload_handler
 from src.search import update_search_config
 
 logger = logging.getLogger(__name__)
@@ -49,6 +50,8 @@ def initialize_managers(base_dir: str, rag_manager=None) -> Dict[str, Any]:
     session_manager = SessionManager(SESSIONS_FILE)
     set_session_manager(session_manager)  # Enable Session.add_message() persistence
     upload_handler = UploadHandler(base_dir, UPLOAD_DIR)
+    session_manager.upload_handler = upload_handler
+    set_upload_handler(upload_handler)
     personal_docs_manager = PersonalDocsManager(PERSONAL_DIR, rag_manager)
     api_key_manager = APIKeyManager(DATA_DIR)
     preset_manager = PresetManager(DATA_DIR)
diff --git a/src/attachment_refs.py b/src/attachment_refs.py
new file mode 100644
index 0000000000..054bea54b9
--- /dev/null
+++ b/src/attachment_refs.py
@@ -0,0 +1,164 @@
+"""Attachment reference helpers for chat storage and tool manifests.
+
+Live model calls may need provider-specific data URLs for the current turn.
+Persisted history and search indexes should keep stable upload references and
+human-readable text instead of duplicating raw media bytes.
+"""
+
+from __future__ import annotations
+
+import json
+import re
+from typing import Any, Iterable
+
+
+DATA_URL_RE = re.compile(
+    r"data:[^;,\s\"']+;base64,[A-Za-z0-9+/=]+",
+    re.IGNORECASE,
+)
+
+MEDIA_BLOCK_TYPES = {
+    "image",
+    "image_url",
+    "input_image",
+    "audio",
+    "input_audio",
+    "file",
+}
+
+
+def strip_inline_data_urls(text: str) -> str:
+    """Replace inline data URLs with a compact marker."""
+    if not isinstance(text, str) or ";base64," not in text:
+        return text
+    return DATA_URL_RE.sub("[inline media omitted from persisted history]", text)
+
+
+def attachment_ref(info: dict[str, Any]) -> dict[str, Any]:
+    """Return the stable attachment reference shape used outside raw uploads."""
+    upload_id = str(info.get("id") or info.get("attachment_id") or "").strip()
+    try:
+        size = int(info.get("size") or 0)
+    except (TypeError, ValueError):
+        size = 0
+    ref = {
+        "type": "attachment_ref",
+        "attachment_id": upload_id,
+        "name": info.get("name") or info.get("original_name") or upload_id,
+        "mime": info.get("mime") or "application/octet-stream",
+        "size": size,
+    }
+    checksum = info.get("checksum_sha256") or info.get("sha256") or info.get("hash")
+    if checksum:
+        ref["checksum_sha256"] = checksum
+    created_at = info.get("created_at") or info.get("uploaded_at")
+    if created_at:
+        ref["created_at"] = created_at
+    for key in ("width", "height", "vision", "vision_model", "gallery_id"):
+        value = info.get(key)
+        if value is not None:
+            ref[key] = value
+    return ref
+
+
+def attachment_refs_from_metadata(metadata: dict[str, Any] | None) -> list[dict[str, Any]]:
+    """Extract attachment refs from message metadata."""
+    attachments = (metadata or {}).get("attachments") or []
+    if not isinstance(attachments, list):
+        return []
+    refs: list[dict[str, Any]] = []
+    for item in attachments:
+        if isinstance(item, dict):
+            ref = attachment_ref(item)
+            if ref.get("attachment_id"):
+                refs.append(ref)
+    return refs
+
+
+def _ref_line(ref: dict[str, Any]) -> str:
+    parts = [f"Attachment: {ref.get('name') or ref.get('attachment_id') or 'upload'}"]
+    if ref.get("attachment_id"):
+        parts.append(f"id={ref['attachment_id']}")
+    if ref.get("mime"):
+        parts.append(f"mime={ref['mime']}")
+    if ref.get("size"):
+        parts.append(f"size={ref['size']} bytes")
+    if ref.get("checksum_sha256"):
+        parts.append(f"sha256={ref['checksum_sha256']}")
+    line = "[" + " | ".join(parts) + "]"
+    if ref.get("vision"):
+        line += f"\n[Attachment description: {str(ref['vision']).strip()}]"
+    return line
+
+
+def _text_from_blocks(blocks: Iterable[Any]) -> str:
+    lines: list[str] = []
+    omitted_media = 0
+    for block in blocks:
+        if isinstance(block, str):
+            lines.append(strip_inline_data_urls(block))
+            continue
+        if not isinstance(block, dict):
+            continue
+        block_type = block.get("type")
+        if block_type == "text":
+            text = block.get("text")
+            if isinstance(text, str) and text:
+                lines.append(strip_inline_data_urls(text))
+        elif block_type == "attachment_ref":
+            lines.append(_ref_line(block))
+        elif block_type in MEDIA_BLOCK_TYPES:
+            omitted_media += 1
+        else:
+            try:
+                encoded = json.dumps(block, ensure_ascii=True, sort_keys=True)
+            except TypeError:
+                encoded = str(block)
+            lines.append(strip_inline_data_urls(encoded))
+    if omitted_media:
+        plural = "s" if omitted_media != 1 else ""
+        lines.append(f"[{omitted_media} inline media payload{plural} omitted]")
+    return "\n".join(line for line in lines if line).strip()
+
+
+def persistable_message_content(
+    content: Any,
+    metadata: dict[str, Any] | None = None,
+) -> str:
+    """Return content safe for DB persistence and FTS indexing.
+
+    Multimodal provider blocks are collapsed to readable text plus stable
+    attachment reference lines from metadata. This avoids storing base64 media
+    in ``chat_messages.content`` while preserving enough context for reloads,
+    search, and later turns.
+    """
+    if isinstance(content, list):
+        text = _text_from_blocks(content)
+        refs = attachment_refs_from_metadata(metadata)
+        ref_lines = [_ref_line(ref) for ref in refs]
+        if ref_lines:
+            text = "\n".join([part for part in (text, "\n".join(ref_lines)) if part]).strip()
+        return text
+    if isinstance(content, str):
+        return strip_inline_data_urls(content)
+    try:
+        return strip_inline_data_urls(json.dumps(content, ensure_ascii=True, sort_keys=True))
+    except TypeError:
+        return strip_inline_data_urls(str(content))
+
+
+def search_index_text(content: Any) -> str:
+    """Best-effort searchable text for legacy stored content."""
+    if isinstance(content, str):
+        raw = content.strip()
+        if raw.startswith("[") and '"type"' in raw:
+            try:
+                parsed = json.loads(content)
+            except (TypeError, ValueError):
+                parsed = None
+            if isinstance(parsed, list):
+                return _text_from_blocks(parsed)
+        return strip_inline_data_urls(content)
+    if isinstance(content, list):
+        return _text_from_blocks(content)
+    return persistable_message_content(content)
diff --git a/src/builtin_actions.py b/src/builtin_actions.py
index 727d2699d1..ca5e5158ff 100644
--- a/src/builtin_actions.py
+++ b/src/builtin_actions.py
@@ -1125,14 +1125,14 @@ def _pull_headers():
             conn = _imap_connect(None, owner=owner)
             try:
                 conn.select("INBOX", readonly=True)
-                status, data = conn.search(None, "ALL")
+                status, data = conn.uid("SEARCH", None, "ALL")
                 if status != "OK" or not data or not data[0]:
                     return results
                 uids = data[0].split()[-300:][::-1]  # newest 300
                 for uid in uids:
                     try:
-                        st, msg_data = conn.fetch(
-                            uid, "(BODY.PEEK[HEADER.FIELDS (FROM)])"
+                        st, msg_data = conn.uid(
+                            "FETCH", uid, "(BODY.PEEK[HEADER.FIELDS (FROM)])"
                         )
                         if st != "OK" or not msg_data or not msg_data[0]:
                             continue
@@ -1214,7 +1214,7 @@ def _fetch_bodies(_msgs):
                     conn2.select("INBOX", readonly=True)
                     for mm in _msgs:
                         try:
-                            st, data = conn2.fetch(mm["uid"], "(BODY.PEEK[TEXT])")
+                            st, data = conn2.uid("FETCH", mm["uid"], "(BODY.PEEK[TEXT])")
                             if st != "OK" or not data or not data[0]:
                                 continue
                             raw = data[0][1] if isinstance(data[0], tuple) else None
@@ -1356,13 +1356,13 @@ async def action_daily_brief(owner: str, **kwargs) -> Tuple[str, bool]:
             conn = _imap_connect(None)
             try:
                 conn.select("INBOX", readonly=True)
-                status, data = conn.search(None, "UNSEEN")
+                status, data = conn.uid("SEARCH", None, "UNSEEN")
                 uids = (data[0].split() if status == "OK" and data and data[0] else [])
                 unread_count = len(uids)
                 # Grab headers for the most recent 5 unread (UIDs increase with arrival)
                 for uid in uids[-5:][::-1]:
                     try:
-                        _, msg_data = conn.fetch(uid, "(BODY.PEEK[HEADER.FIELDS (FROM SUBJECT)])")
+                        _, msg_data = conn.uid("FETCH", uid, "(BODY.PEEK[HEADER.FIELDS (FROM SUBJECT)])")
                         if not msg_data or not msg_data[0]:
                             continue
                         hdr = msg_data[0][1] if isinstance(msg_data[0], tuple) else msg_data[0]
diff --git a/src/builtin_mcp.py b/src/builtin_mcp.py
index 2a4b748eee..b777e99a4b 100644
--- a/src/builtin_mcp.py
+++ b/src/builtin_mcp.py
@@ -104,6 +104,21 @@ def _spawn_bg(coro) -> asyncio.Task:
     return task
 
 
+def builtin_python_env(base_dir: str) -> dict[str, str]:
+    """Environment for built-in Python MCP subprocesses.
+
+    The app root must be importable so mcp_servers can import local modules, but
+    replacing PYTHONPATH entirely hides site-packages in container/dev launches
+    that rely on PYTHONPATH for their active environment.
+    """
+    existing = os.environ.get("PYTHONPATH", "")
+    parts = [base_dir]
+    for item in existing.split(os.pathsep):
+        if item and item not in parts:
+            parts.append(item)
+    return {"PYTHONPATH": os.pathsep.join(parts)}
+
+
 async def register_builtin_servers(mcp_manager):
     """Connect all built-in MCP servers to the manager."""
     if MCP_DISABLED:
@@ -121,7 +136,7 @@ async def _connect_python_server(server_id: str, script_path: str, name: str):
                 transport="stdio",
                 command=python,
                 args=[script_path],
-                env={"PYTHONPATH": base_dir},
+                env=builtin_python_env(base_dir),
             )
             if ok:
                 logger.info(f"Built-in MCP server registered: {name}")
diff --git a/src/caldav_sync.py b/src/caldav_sync.py
index f91ebc1a0a..47fb3333b3 100644
--- a/src/caldav_sync.py
+++ b/src/caldav_sync.py
@@ -280,214 +280,216 @@ def _sync_blocking(owner: str, url: str, username: str, password: str, account_i
     result = {"calendars": 0, "events": 0, "deleted": 0, "errors": []}
 
     client = _build_dav_client(url, username, password)
-
-    # Discovery: try principal → calendars first; if the server doesn't
-    # support discovery (or the URL points directly at a calendar), fall
-    # back to treating the URL as a single calendar.
-    calendars = []
     try:
-        principal = client.principal()
-        calendars = principal.calendars()
-    except (AuthorizationError, NotFoundError) as e:
-        result["errors"].append(f"Discovery failed: {e}")
-        return result
-    except Exception as e:
-        logger.info(f"CalDAV principal discovery failed, trying URL as calendar: {e}")
+        # Discovery: try principal → calendars first; if the server doesn't
+        # support discovery (or the URL points directly at a calendar), fall
+        # back to treating the URL as a single calendar.
+        calendars = []
         try:
-            calendars = [_open_url_as_calendar(client, url)]
-        except Exception as e2:
-            result["errors"].append(f"Could not open URL as calendar: {e2}")
-            return result
-
-    if not calendars:
-        try:
-            calendars = [_open_url_as_calendar(client, url)]
+            principal = client.principal()
+            calendars = principal.calendars()
+        except (AuthorizationError, NotFoundError) as e:
+            result["errors"].append(f"Discovery failed: {e}")
+            return result          # outer finally will call client.close()
         except Exception as e:
-            result["errors"].append(f"No calendars and URL fallback failed: {e}")
-            return result
-
-    start = datetime.utcnow() - timedelta(days=_LOOKBACK_DAYS)
-    end = datetime.utcnow() + timedelta(days=_LOOKAHEAD_DAYS)
+            logger.info(f"CalDAV principal discovery failed, trying URL as calendar: {e}")
+            try:
+                calendars = [_open_url_as_calendar(client, url)]
+            except Exception as e2:
+                result["errors"].append(f"Could not open URL as calendar: {e2}")
+                return result      # outer finally will call client.close()
 
-    db = SessionLocal()
-    try:
-        for remote_cal in calendars:
+        if not calendars:
             try:
-                remote_url = str(remote_cal.url)
-                cal_id = _stable_cal_id(remote_url, owner=owner, account_id=account_id)
-                display_name = (remote_cal.name or "").strip() or "CalDAV"
-
-                local_cal = db.query(CalendarCal).filter(
-                    CalendarCal.id == cal_id,
-                    CalendarCal.owner == owner,
-                ).first()
-                if not local_cal:
-                    local_cal = CalendarCal(
-                        id=cal_id,
-                        owner=owner,
-                        name=display_name,
-                        color="#5b8abf",
-                        source="caldav",
-                        account_id=account_id or None,
-                        caldav_base_url=remote_url,
-                    )
-                    db.add(local_cal)
-                    db.commit()
-                else:
-                    # Refresh display name and stamp CalDAV metadata if missing.
-                    changed = False
-                    if local_cal.name != display_name:
-                        local_cal.name = display_name
-                        changed = True
-                    if account_id and not local_cal.account_id:
-                        local_cal.account_id = account_id
-                        changed = True
-                    if local_cal.caldav_base_url != remote_url:
-                        local_cal.caldav_base_url = remote_url
-                        changed = True
-                    if changed:
-                        db.commit()
-                result["calendars"] += 1
-
-                # Fetch events in window. `date_search` returns CalendarObject
-                # resources; each may contain one VEVENT (most servers) or
-                # several (rare).
-                from icalendar import Calendar as iCal
-
-                seen_uids = set()
-                # Track events added to the session but not yet committed so
-                # duplicate UIDs within the same batch are updated, not re-inserted
-                # (which would violate the UNIQUE constraint on commit).
-                pending: dict = {}
-                parse_failed = False
-                try:
-                    objs = remote_cal.date_search(start=start, end=end, expand=False)
-                except Exception as e:
-                    result["errors"].append(f"{display_name}: date_search failed ({e})")
-                    continue
+                calendars = [_open_url_as_calendar(client, url)]
+            except Exception as e:
+                result["errors"].append(f"No calendars and URL fallback failed: {e}")
+                return result      # outer finally will call client.close()
+
+        start = datetime.utcnow() - timedelta(days=_LOOKBACK_DAYS)
+        end = datetime.utcnow() + timedelta(days=_LOOKAHEAD_DAYS)
 
-                for obj in objs:
+        db = SessionLocal()        # if this raises, outer finally still calls client.close()
+        try:
+            for remote_cal in calendars:
+                try:
+                    remote_url = str(remote_cal.url)
+                    cal_id = _stable_cal_id(remote_url, owner=owner, account_id=account_id)
+                    display_name = (remote_cal.name or "").strip() or "CalDAV"
+
+                    local_cal = db.query(CalendarCal).filter(
+                        CalendarCal.id == cal_id,
+                        CalendarCal.owner == owner,
+                    ).first()
+                    if not local_cal:
+                        local_cal = CalendarCal(
+                            id=cal_id,
+                            owner=owner,
+                            name=display_name,
+                            color="#5b8abf",
+                            source="caldav",
+                            account_id=account_id or None,
+                            caldav_base_url=remote_url,
+                        )
+                        db.add(local_cal)
+                        db.commit()
+                    else:
+                        # Refresh display name and stamp CalDAV metadata if missing.
+                        changed = False
+                        if local_cal.name != display_name:
+                            local_cal.name = display_name
+                            changed = True
+                        if account_id and not local_cal.account_id:
+                            local_cal.account_id = account_id
+                            changed = True
+                        if local_cal.caldav_base_url != remote_url:
+                            local_cal.caldav_base_url = remote_url
+                            changed = True
+                        if changed:
+                            db.commit()
+                    result["calendars"] += 1
+
+                    # Fetch events in window. `date_search` returns CalendarObject
+                    # resources; each may contain one VEVENT (most servers) or
+                    # several (rare).
+                    from icalendar import Calendar as iCal
+
+                    seen_uids = set()
+                    # Track events added to the session but not yet committed so
+                    # duplicate UIDs within the same batch are updated, not re-inserted
+                    # (which would violates the UNIQUE constraint on commit).
+                    pending: dict = {}
+                    parse_failed = False
                     try:
-                        ical = iCal.from_ical(obj.data)
+                        objs = remote_cal.date_search(start=start, end=end, expand=False)
                     except Exception as e:
-                        result["errors"].append(f"{display_name}: parse failed ({e})")
-                        parse_failed = True
+                        result["errors"].append(f"{display_name}: date_search failed ({e})")
                         continue
 
-                    for comp in ical.walk():
-                        if comp.name != "VEVENT":
+                    for obj in objs:
+                        try:
+                            ical = iCal.from_ical(obj.data)
+                        except Exception as e:
+                            result["errors"].append(f"{display_name}: parse failed ({e})")
+                            parse_failed = True
                             continue
-                        uid_val = str(comp.get("uid", "")) or str(uuid.uuid4())
-                        seen_uids.add(uid_val)
 
-                        dtstart_p = comp.get("dtstart")
-                        if not dtstart_p:
-                            continue
-                        start_dt, all_day = _to_utc_naive(dtstart_p.dt)
-
-                        dtend_p = comp.get("dtend")
-                        if dtend_p:
-                            end_dt, _ = _to_utc_naive(dtend_p.dt)
-                        elif all_day:
-                            end_dt = start_dt + timedelta(days=1)
-                        else:
-                            end_dt = start_dt + timedelta(hours=1)
-                        # A synced event with DTEND <= DTSTART (e.g. a single-day
-                        # all-day event whose source wrote DTEND equal to DTSTART)
-                        # would be stored zero-duration and silently dropped by the
-                        # list_events overlap filter. Clamp to a positive span.
-                        end_dt = _ensure_positive_duration(start_dt, end_dt, all_day)
-
-                        # is_utc reflects whether the source carried a TZ
-                        # we converted from. All-day = no TZ semantics.
-                        row_is_utc = (
-                            not all_day
-                            and isinstance(dtstart_p.dt, datetime)
-                            and dtstart_p.dt.tzinfo is not None
-                        )
-
-                        summary = str(comp.get("summary", ""))
-                        description = str(comp.get("description", ""))
-                        location = str(comp.get("location", ""))
-                        rrule = (
-                            comp.get("rrule").to_ical().decode()
-                            if comp.get("rrule")
-                            else ""
-                        )
+                        for comp in ical.walk():
+                            if comp.name != "VEVENT":
+                                continue
+                            uid_val = str(comp.get("uid", "")) or str(uuid.uuid4())
+                            seen_uids.add(uid_val)
 
-                        existing = _find_existing_event(db, pending, uid_val, local_cal.id)
-                        if existing:
-                            if existing.caldav_sync_pending in {"create", "update"}:
-                                result["events"] += 1
+                            dtstart_p = comp.get("dtstart")
+                            if not dtstart_p:
                                 continue
-                            existing.calendar_id = local_cal.id
-                            existing.summary = summary
-                            existing.description = description
-                            existing.location = location
-                            existing.dtstart = start_dt
-                            existing.dtend = end_dt
-                            existing.all_day = all_day
-                            existing.is_utc = row_is_utc
-                            existing.rrule = rrule
-                            existing.origin = "caldav"
-                            existing.remote_href = str(getattr(obj, "url", "") or "") or None
-                            existing.remote_etag = _event_etag(obj) or None
-                            existing.caldav_sync_pending = None
-                        else:
-                            new_ev = CalendarEvent(
-                                uid=uid_val,
-                                calendar_id=local_cal.id,
-                                summary=summary,
-                                description=description,
-                                location=location,
-                                dtstart=start_dt,
-                                dtend=end_dt,
-                                all_day=all_day,
-                                is_utc=row_is_utc,
-                                rrule=rrule,
-                                origin="caldav",
-                                remote_href=str(getattr(obj, "url", "") or "") or None,
-                                remote_etag=_event_etag(obj) or None,
+                            start_dt, all_day = _to_utc_naive(dtstart_p.dt)
+
+                            dtend_p = comp.get("dtend")
+                            if dtend_p:
+                                end_dt, _ = _to_utc_naive(dtend_p.dt)
+                            elif all_day:
+                                end_dt = start_dt + timedelta(days=1)
+                            else:
+                                end_dt = start_dt + timedelta(hours=1)
+                            # A synced event with DTEND <= DTSTART (e.g. a single-day
+                            # all-day event whose source wrote DTEND equal to DTSTART)
+                            # would be stored zero-duration and silently dropped by the
+                            # list_events overlap filter. Clamp to a positive span.
+                            end_dt = _ensure_positive_duration(start_dt, end_dt, all_day)
+
+                            # is_utc reflects whether the source carried a TZ
+                            # we converted from. All-day = no TZ semantics.
+                            row_is_utc = (
+                                not all_day
+                                and isinstance(dtstart_p.dt, datetime)
+                                and dtstart_p.dt.tzinfo is not None
                             )
-                            db.add(new_ev)
-                            pending[uid_val] = new_ev
-                        result["events"] += 1
-                db.commit()
-
-                # Prune locally-cached CalDAV events that vanished
-                # upstream (only within our sync window — events outside
-                # the window aren't in `objs`, so we'd false-delete them).
-                # Only rows we previously pulled from the server (origin=="caldav")
-                # are prunable; locally-created events (agent / email triage / a
-                # UI event whose write-back failed) carry origin NULL and must
-                # never be deleted just because the server didn't return them.
-                # Skip the prune on any parse failure: seen_uids is then an
-                # incomplete view of the server, so pruning against it would
-                # delete events that still exist upstream but could not be read
-                # (the empty-seen_uids case wipes the whole window; a partial
-                # failure deletes just the unreadable rows).
-                if _should_prune_window(seen_uids, parse_failed):
-                    stale = db.query(CalendarEvent).filter(
-                        CalendarEvent.calendar_id == local_cal.id,
-                        CalendarEvent.origin == "caldav",
-                        CalendarEvent.dtstart >= start,
-                        CalendarEvent.dtstart <= end,
-                        CalendarEvent.remote_href.isnot(None),
-                        CalendarEvent.caldav_sync_pending.is_(None),
-                        ~CalendarEvent.uid.in_(seen_uids) if seen_uids else CalendarEvent.uid.isnot(None),
-                    ).all()
-                    for ev in stale:
-                        db.delete(ev)
-                    result["deleted"] += len(stale)
+
+                            summary = str(comp.get("summary", ""))
+                            description = str(comp.get("description", ""))
+                            location = str(comp.get("location", ""))
+                            rrule = (
+                                comp.get("rrule").to_ical().decode()
+                                if comp.get("rrule")
+                                else ""
+                            )
+
+                            existing = _find_existing_event(db, pending, uid_val, local_cal.id)
+                            if existing:
+                                if existing.caldav_sync_pending in {"create", "update"}:
+                                    result["events"] += 1
+                                    continue
+                                existing.calendar_id = local_cal.id
+                                existing.summary = summary
+                                existing.description = description
+                                existing.location = location
+                                existing.dtstart = start_dt
+                                existing.dtend = end_dt
+                                existing.all_day = all_day
+                                existing.is_utc = row_is_utc
+                                existing.rrule = rrule
+                                existing.origin = "caldav"
+                                existing.remote_href = str(getattr(obj, "url", "") or "") or None
+                                existing.remote_etag = _event_etag(obj) or None
+                                existing.caldav_sync_pending = None
+                            else:
+                                new_ev = CalendarEvent(
+                                    uid=uid_val,
+                                    calendar_id=local_cal.id,
+                                    summary=summary,
+                                    description=description,
+                                    location=location,
+                                    dtstart=start_dt,
+                                    dtend=end_dt,
+                                    all_day=all_day,
+                                    is_utc=row_is_utc,
+                                    rrule=rrule,
+                                    origin="caldav",
+                                    remote_href=str(getattr(obj, "url", "") or "") or None,
+                                    remote_etag=_event_etag(obj) or None,
+                                )
+                                db.add(new_ev)
+                                pending[uid_val] = new_ev
+                            result["events"] += 1
                     db.commit()
-            except Exception as e:
-                logger.exception("CalDAV sync failed for one calendar")
-                result["errors"].append(str(e)[:200])
-                db.rollback()
-    finally:
-        db.close()
 
-    return result
+                    # Prune locally-cached CalDAV events that vanished
+                    # upstream (only within our sync window — events outside
+                    # the window aren't in `objs`, so we'd false-delete them).
+                    # Only rows we previously pulled from the server (origin=="caldav")
+                    # are prunable; locally-created events (agent / email triage / a
+                    # UI event whose write-back failed) carry origin NULL and must
+                    # never be deleted just because the server didn't return them.
+                    # Skip the prune on any parse failure: seen_uids is then an
+                    # incomplete view of the server, so pruning against it would
+                    # delete events that still exist upstream but could not be read
+                    # (the empty-seen_uids case wipes the whole window; a partial
+                    # failure deletes just the unreadable rows).
+                    if _should_prune_window(seen_uids, parse_failed):
+                        stale = db.query(CalendarEvent).filter(
+                            CalendarEvent.calendar_id == local_cal.id,
+                            CalendarEvent.origin == "caldav",
+                            CalendarEvent.dtstart >= start,
+                            CalendarEvent.dtstart <= end,
+                            CalendarEvent.remote_href.isnot(None),
+                            CalendarEvent.caldav_sync_pending.is_(None),
+                            ~CalendarEvent.uid.in_(seen_uids) if seen_uids else CalendarEvent.uid.isnot(None),
+                        ).all()
+                        for ev in stale:
+                            db.delete(ev)
+                        result["deleted"] += len(stale)
+                        db.commit()
+                except Exception as e:
+                    logger.exception("CalDAV sync failed for one calendar")
+                    result["errors"].append(str(e)[:200])
+                    db.rollback()
+        finally:
+            db.close()             # NOT client.close() here anymore
+
+        return result
+    finally:
+        client.close()             # always called
 
 
 def _event_payload(ev) -> dict:
diff --git a/src/caldav_writeback.py b/src/caldav_writeback.py
index b1cf288b16..2d5781091d 100644
--- a/src/caldav_writeback.py
+++ b/src/caldav_writeback.py
@@ -192,11 +192,14 @@ def _writeback_blocking(local_cal_id, ev, delete, url, username, password,
     # Redirects disabled here too: the write-back path opens its own DAVClient,
     # so it needs the same SSRF-via-redirect protection as the pull path.
     client = _build_dav_client(url, username, password)
-    calendars = _discover_calendars(client)
-    if not calendars:
-        return {"ok": False, "error": "no remote calendars discovered"}
-    return push_event(calendars, local_cal_id, ev, delete=delete,
-                      owner=owner, account_id=account_id)
+    try:
+        calendars = _discover_calendars(client)
+        if not calendars:
+            return {"ok": False, "error": "no remote calendars discovered"}
+        return push_event(calendars, local_cal_id, ev, delete=delete,
+                          owner=owner, account_id=account_id)
+    finally:
+        client.close()
 
 
 def _persist_writeback_result(owner: str, calendar_id: str, uid: str, result: dict, *, delete: bool) -> None:
diff --git a/src/chat_handler.py b/src/chat_handler.py
index 9df6f7ce6f..f9b2a21930 100644
--- a/src/chat_handler.py
+++ b/src/chat_handler.py
@@ -191,6 +191,8 @@ async def preprocess_message(
                         "name": fi.get("name") or fi.get("original_name") or fi["id"],
                         "mime": fi.get("mime", ""),
                         "size": fi.get("size", 0),
+                        "checksum_sha256": fi.get("checksum_sha256") or fi.get("hash"),
+                        "created_at": fi.get("created_at") or fi.get("uploaded_at"),
                         "width": fi.get("width"),
                         "height": fi.get("height"),
                     })
diff --git a/src/config.py b/src/config.py
index d5cfa21a7b..fa8b17ce5d 100644
--- a/src/config.py
+++ b/src/config.py
@@ -27,7 +27,6 @@ class DataConfig(BaseSettings):
     uploads_dir: Path = Field(default=Path(_DATA_DIR_CONST) / "uploads", description="Directory for uploaded files")
     sessions_file: Path = Field(default=Path(_DATA_DIR_CONST) / "sessions.json", description="Sessions storage file")
     memory_file: Path = Field(default=Path(_DATA_DIR_CONST) / "memory.json", description="Memory storage file")
-    memory_doc: Path = Field(default=Path(_DATA_DIR_CONST) / "memory_doc.md", description="Memory document file")
     personal_dir: Path = Field(default=Path(_DATA_DIR_CONST) / "personal_docs", description="Personal documents directory")
     runbook_dir: Path = Field(default=Path(_DATA_DIR_CONST) / "personal_docs" / "runbook", description="Runbook directory")
     
@@ -162,7 +161,6 @@ def set_data_paths(cls, v, info):
             "uploads_dir": data_dir / "uploads",
             "sessions_file": data_dir / "sessions.json",
             "memory_file": data_dir / "memory.json",
-            "memory_doc": data_dir / "memory_doc.md",
             "personal_dir": data_dir / "personal_docs",
             "runbook_dir": data_dir / "personal_docs" / "runbook",
             "max_upload_size": max_upload_size,
diff --git a/src/constants.py b/src/constants.py
index eceeb6eb09..f19fb54615 100644
--- a/src/constants.py
+++ b/src/constants.py
@@ -17,7 +17,6 @@
 # re-deriving paths from __file__ or a relative "data" literal.
 SESSIONS_FILE = os.path.join(DATA_DIR, "sessions.json")
 MEMORY_FILE = os.path.join(DATA_DIR, "memory.json")
-MEMORY_DOC = os.path.join(DATA_DIR, "memory_doc.md")
 PERSONAL_DIR = os.path.join(DATA_DIR, "personal_docs")
 RUNBOOK_DIR = os.path.join(PERSONAL_DIR, "runbook")
 UPLOAD_DIR = os.path.join(DATA_DIR, "uploads")
diff --git a/src/copilot.py b/src/copilot.py
index 62d2b8ca24..92c9c0a21d 100644
--- a/src/copilot.py
+++ b/src/copilot.py
@@ -230,7 +230,10 @@ def request_flags(messages) -> tuple:
     """
     msgs = messages or []
     last = msgs[-1] if msgs else None
-    agent = bool(last) and last.get("role") != "user"
+    # A message element can be a non-dict (clients send `"messages": ["hi"]`);
+    # the vision loop below already guards each element with isinstance, so do
+    # the same here rather than call .get() on a bare string.
+    agent = isinstance(last, dict) and last.get("role") != "user"
     vision = False
     for m in msgs:
         content = m.get("content") if isinstance(m, dict) else None
diff --git a/src/document_processor.py b/src/document_processor.py
index e96ec999c1..8025e22e03 100644
--- a/src/document_processor.py
+++ b/src/document_processor.py
@@ -440,7 +440,10 @@ def build_user_content(
             try:
                 with open(path, "rb") as image_file:
                     encoded_string = base64.b64encode(image_file.read()).decode("utf-8")
-                image_format = ext[1:]
+                # Extensionless uploads (e.g. a pasted screenshot) have no ext,
+                # so fall back to the resolved MIME subtype rather than emitting
+                # an invalid "data:image/;base64," with an empty subtype.
+                image_format = ext[1:] or (mime.split("/", 1)[1] if mime.startswith("image/") else "png")
                 content.append({
                     "type": "image_url",
                     "image_url": {"url": f"data:image/{image_format};base64,{encoded_string}"},
@@ -456,7 +459,7 @@ def build_user_content(
             try:
                 with open(path, "rb") as audio_file:
                     encoded_string = base64.b64encode(audio_file.read()).decode("utf-8")
-                audio_format = ext[1:]
+                audio_format = ext[1:] or (mime.split("/", 1)[1] if mime.startswith("audio/") else "mpeg")
                 content.append({
                     "type": "audio",
                     "audio": {"url": f"data:audio/{audio_format};base64,{encoded_string}"},
diff --git a/src/llm_core.py b/src/llm_core.py
index d8f94dfb74..af1958f16f 100644
--- a/src/llm_core.py
+++ b/src/llm_core.py
@@ -766,6 +766,36 @@ def apply_kimi_code_headers(headers: Optional[Dict], url: str) -> Dict[str, str]
     return h
 
 
+async def apply_kimi_code_headers_async(client, headers: Optional[Dict], url: str) -> Dict[str, str]:
+    """Pick a Kimi Code User-Agent without blocking the event loop."""
+    h = dict(headers or {})
+    if not _is_kimi_code_url(url):
+        return h
+    base_key = _kimi_code_base_key(url)
+    cached = _kimi_code_ua_cache.get(base_key)
+    if cached:
+        h["User-Agent"] = cached
+        return h
+    models_url = base_key.rstrip("/") + "/models"
+    for ua in KIMI_CODE_USER_AGENTS:
+        trial = dict(h)
+        trial["User-Agent"] = ua
+        try:
+            r = await client.get(models_url, headers=trial, timeout=8)
+        except Exception:
+            continue
+        if _is_kimi_code_access_denied(r.status_code, r.content):
+            logger.debug("Kimi Code rejected User-Agent %s (403), trying next", ua)
+            continue
+        if r.status_code < 400:
+            _remember_kimi_code_user_agent(url, ua)
+            h["User-Agent"] = ua
+            return h
+        break
+    h.setdefault("User-Agent", KIMI_CODE_USER_AGENT)
+    return h
+
+
 def httpx_get_kimi_aware(url: str, headers: Optional[Dict], **kwargs):
     h = apply_kimi_code_headers(headers, url)
     if not _is_kimi_code_url(url):
@@ -799,7 +829,7 @@ def httpx_post_kimi_aware(url: str, headers: Optional[Dict], **kwargs):
 
 
 async def httpx_post_kimi_aware_async(client, url: str, headers: Optional[Dict], **kwargs):
-    h = apply_kimi_code_headers(headers, url)
+    h = await apply_kimi_code_headers_async(client, headers, url)
     if not _is_kimi_code_url(url):
         return await client.post(url, headers=h, **kwargs)
     last = None
@@ -2466,9 +2496,9 @@ def _format_routed_content(parts: List[Tuple[str, bool]]) -> List[str]:
             events.append(_stream_delta_event(part))
         return events
 
-    h = apply_kimi_code_headers(h, target_url)
     try:
         client = _get_http_client()
+        h = await apply_kimi_code_headers_async(client, h, target_url)
         async with client.stream('POST', target_url, json=payload, headers=h, timeout=stream_timeout) as r:
             _clear_host_dead(target_url)
             if r.status_code != 200:
diff --git a/src/mcp_manager.py b/src/mcp_manager.py
index 8f4322375d..b71f602ab0 100644
--- a/src/mcp_manager.py
+++ b/src/mcp_manager.py
@@ -9,7 +9,9 @@
 import logging
 import os
 import re
+import asyncio 
 from typing import Any, Dict, List, Optional, Set, Tuple
+from src.database import McpServer, SessionLocal
 
 from src.runtime_paths import get_app_root
 
@@ -192,57 +194,65 @@ async def _connect_stdio(self, server_id: str, name: str, command: str, args: Li
             )
 
             stack = AsyncExitStack()
+            registered = False
+
             try:
                 transport = await stack.enter_async_context(stdio_client(server_params))
                 read_stream, write_stream = transport
                 session = await stack.enter_async_context(ClientSession(read_stream, write_stream))
 
                 await session.initialize()
-
-                # Discover tools
                 tools_result = await session.list_tools()
-            except Exception:
-                await stack.aclose()
-                raise
-            tools = []
-            for tool in tools_result.tools:
-                tools.append({
-                    "name": tool.name,
-                    "description": tool.description or "",
-                    "input_schema": tool.inputSchema if hasattr(tool, 'inputSchema') else {},
-                    # MCP tool annotations (readOnlyHint / destructiveHint) drive
-                    # plan-mode read-only gating. Absent on many servers, so we
-                    # fall back to a name heuristic in mcp_tool_is_readonly().
-                    "annotations": getattr(tool, 'annotations', None),
-                })
 
-            self._sessions[server_id] = session
-            self._stacks[server_id] = stack
-            self._tools[server_id] = tools
-            # Extract identity hints from env vars (e.g. email address, API name)
-            # so tool descriptions can distinguish between multiple instances of
-            # the same MCP server (e.g. two email accounts).
-            identity_hints = []
-            for k, v in (env or {}).items():
-                k_lower = k.lower()
-                if any(x in k_lower for x in ['email_address', 'account', 'user', 'username']):
-                    identity_hints.append(v)
-            identity = ", ".join(identity_hints) if identity_hints else ""
+                tools = []
+                for tool in tools_result.tools:
+                    tools.append({
+                        "name": tool.name,
+                        "description": tool.description or "",
+                        "input_schema": tool.inputSchema if hasattr(tool, "inputSchema") else {},
+                        # MCP tool annotations (readOnlyHint / destructiveHint) drive
+                        # plan-mode read-only gating. Absent on many servers, so we
+                        # fall back to a name heuristic in mcp_tool_is_readonly().
+                        "annotations": getattr(tool, "annotations", None),
+                    })
+
+                # Extract identity hints from env vars (e.g. email address, API name)
+                # so tool descriptions can distinguish between multiple instances of
+                # the same MCP server (e.g. two email accounts).
+                identity_hints = []
+                for k, v in (env or {}).items():
+                    k_lower = k.lower()
+                    if any(x in k_lower for x in ["email_address", "account", "user", "username"]):
+                        identity_hints.append(v)
+                identity = ", ".join(identity_hints) if identity_hints else ""
+
+                self._sessions[server_id] = session
+                self._stacks[server_id] = stack
+                self._tools[server_id] = tools
+                self._connections[server_id] = {
+                    "status": "connected",
+                    "name": name,
+                    "transport": "stdio",
+                    "tool_count": len(tools),
+                    "identity": identity,
+                }
 
-            self._connections[server_id] = {
-                "status": "connected",
-                "name": name,
-                "transport": "stdio",
-                "tool_count": len(tools),
-                "identity": identity,
-            }
+                registered = True
+
+            finally:
+                if not registered:
+                    await stack.aclose()
 
             logger.info(f"MCP server connected: {name} ({server_id}) - {len(tools)} tools via stdio")
             return True
 
         except ImportError:
             logger.warning("MCP package not installed. Install with: pip install mcp")
-            self._connections[server_id] = {"status": "error", "error": "mcp package not installed", "name": name}
+            self._connections[server_id] = {
+                "status": "error",
+                "error": "mcp package not installed",
+                "name": name,
+            }
             return False
 
     async def _connect_sse(self, server_id: str, name: str, url: str) -> bool:
@@ -253,42 +263,46 @@ async def _connect_sse(self, server_id: str, name: str, url: str) -> bool:
             from contextlib import AsyncExitStack
 
             stack = AsyncExitStack()
+            registered = False
+
             try:
                 transport = await stack.enter_async_context(sse_client(url))
                 read_stream, write_stream = transport
                 session = await stack.enter_async_context(ClientSession(read_stream, write_stream))
 
                 await session.initialize()
-
-                # Discover tools
                 tools_result = await session.list_tools()
-            except Exception:
-                await stack.aclose()
-                raise
-            tools = []
-            for tool in tools_result.tools:
-                tools.append({
-                    "name": tool.name,
-                    "description": tool.description or "",
-                    "input_schema": tool.inputSchema if hasattr(tool, 'inputSchema') else {},
-                    # MCP tool annotations (readOnlyHint / destructiveHint) drive
-                    # plan-mode read-only gating. Absent on many servers, so we
-                    # fall back to a name heuristic in mcp_tool_is_readonly().
-                    "annotations": getattr(tool, 'annotations', None),
-                })
 
-            self._sessions[server_id] = session
-            self._stacks[server_id] = stack
-            self._tools[server_id] = tools
-            self._connections[server_id] = {
-                "status": "connected",
-                "name": name,
-                "transport": "sse",
-                "tool_count": len(tools),
-            }
+                tools = []
+                for tool in tools_result.tools:
+                    tools.append({
+                        "name": tool.name,
+                        "description": tool.description or "",
+                        "input_schema": tool.inputSchema if hasattr(tool, 'inputSchema') else {},
+                        # MCP tool annotations (readOnlyHint / destructiveHint) drive
+                        # plan-mode read-only gating. Absent on many servers, so we
+                        # fall back to a name heuristic in mcp_tool_is_readonly().
+                        "annotations": getattr(tool, 'annotations', None),
+                    })
+
+                self._sessions[server_id] = session
+                self._stacks[server_id] = stack
+                self._tools[server_id] = tools
+                self._connections[server_id] = {
+                    "status": "connected",
+                    "name": name,
+                    "transport": "sse",
+                    "tool_count": len(tools),
+                }
 
-            logger.info(f"MCP server connected: {name} ({server_id}) - {len(tools)} tools via SSE")
-            return True
+                registered = True
+
+                logger.info(f"MCP server connected: {name} ({server_id}) - {len(tools)} tools via SSE")
+                return True
+
+            finally:
+                if not registered:
+                    await stack.aclose()
 
         except ImportError:
             logger.warning("MCP package not installed. Install with: pip install mcp")
@@ -340,34 +354,58 @@ def _on_redirect(auth_url):
 
             provider = build_provider(server_id, url, on_redirect=_on_redirect)
             stack = AsyncExitStack()
-            transport = await stack.enter_async_context(streamablehttp_client(url, auth=provider))
-            read_stream, write_stream, _get_session_id = transport
-            session = await stack.enter_async_context(ClientSession(read_stream, write_stream))
-            await session.initialize()
-
-            tools_result = await session.list_tools()
-            tools = []
-            for tool in tools_result.tools:
-                tools.append({
-                    "name": tool.name,
-                    "description": tool.description or "",
-                    "input_schema": tool.inputSchema if hasattr(tool, "inputSchema") else {},
-                })
+            registered = False
+            try:
+                transport = await stack.enter_async_context(streamablehttp_client(url, auth=provider))
+                read_stream, write_stream, _get_session_id = transport
+                session = await stack.enter_async_context(ClientSession(read_stream, write_stream))
+                await session.initialize()
 
-            self._sessions[server_id] = session
-            self._stacks[server_id] = stack
-            self._tools[server_id] = tools
-            self._connections[server_id] = {
-                "status": "connected", "name": name, "transport": "http",
-                "tool_count": len(tools),
-            }
-            clear_auth_url(server_id)
-            # Tools changed (this can complete after connect_server already
-            # returned, via the background OAuth flow), so bump the generation
-            # to invalidate the tool-prompt cache.
-            self._generation += 1
-            logger.info(f"MCP server connected: {name} ({server_id}) - {len(tools)} tools via http")
-            return True
+                tools_result = await session.list_tools()
+                tools = []
+                for tool in tools_result.tools:
+                    tools.append({
+                        "name": tool.name,
+                        "description": tool.description or "",
+                        "input_schema": tool.inputSchema if hasattr(tool, "inputSchema") else {},
+                    })
+
+                self._sessions[server_id] = session
+                self._stacks[server_id] = stack
+                self._tools[server_id] = tools
+                self._connections[server_id] = {
+                    "status": "connected", "name": name, "transport": "http",
+                    "tool_count": len(tools),
+                }
+                registered = True
+
+                clear_auth_url(server_id)
+                # Tools changed (this can complete after connect_server already
+                # returned, via the background OAuth flow), so bump the generation
+                # to invalidate the tool-prompt cache.
+                self._generation += 1
+                logger.info(f"MCP server connected: {name} ({server_id}) - {len(tools)} tools via http")
+                return True
+            finally:
+                # _connect_stdio and _connect_sse already guard their stack this way; http
+                # was the one transport that did not. A failed connect left the stack -- and
+                # the anyio task group entered inside it -- to be finalized by the garbage
+                # collector, from a DIFFERENT task than the one that entered it.
+                #
+                # anyio's CancelScope.__exit__ then raises "Attempted to exit cancel scope in
+                # a different task than it was entered in" BEFORE it can remove the host task
+                # from _tasks, so _deliver_cancellation re-arms call_soon on every iteration
+                # of the event loop, forever. The loop never sleeps again:
+                # epoll_wait(timeout=0) at ~149k calls/sec returning zero events, and the
+                # process pins a CPU core for the rest of its life.
+                #
+                # `finally` rather than `except`, deliberately: the failure arrives as
+                # CancelledError, which is a BaseException, so `except Exception` never sees
+                # it. (Observed in production: the outer handler below logged nothing at all
+                # across the entire lifetime of the process, because it could not catch what
+                # was being raised.)
+                if not registered:
+                    await stack.aclose()
         except ImportError:
             logger.warning("MCP package not installed. Install with: pip install mcp")
             self._connections[server_id] = {"status": "error", "error": "mcp package not installed", "name": name}
@@ -409,17 +447,29 @@ async def disconnect_all(self):
         for sid in ids:
             await self.disconnect_server(sid)
 
-    async def connect_all_enabled(self):
-        """Connect to all enabled MCP servers from the database."""
-        from src.database import McpServer, SessionLocal
 
+    async def connect_all_enabled(self):
         db = SessionLocal()
         try:
             servers = db.query(McpServer).filter(McpServer.is_enabled == True).all()
-            for srv in servers:
-                args = json.loads(srv.args) if srv.args else []
-                env = json.loads(srv.env) if srv.env else {}
-                await self.connect_server(
+
+            tasks = [
+                asyncio.create_task(self._connect_with_timeout(srv))
+                for srv in servers
+            ]
+
+            await asyncio.gather(*tasks)
+        finally:
+            db.close()
+
+
+    async def _connect_with_timeout(self, srv):
+        args = json.loads(srv.args) if srv.args else []
+        env = json.loads(srv.env) if srv.env else {}
+
+        try:
+            await asyncio.wait_for(
+                self.connect_server(
                     server_id=srv.id,
                     name=srv.name,
                     transport=srv.transport,
@@ -427,9 +477,16 @@ async def connect_all_enabled(self):
                     args=args,
                     env=env,
                     url=srv.url,
-                )
-        finally:
-            db.close()
+                ),
+                timeout=20,
+            )
+        except asyncio.TimeoutError:
+            logger.warning("Timed out connecting to %s", srv.name)
+            self._connections[srv.id] = {
+                "status": "timeout",
+                "error": f"Timed out after 20 seconds",
+                "name": srv.name,
+            }
 
     async def call_tool(self, qualified_name: str, arguments: Dict) -> Dict:
         """Call an MCP tool by its qualified name (mcp__{server_id}__{tool_name}).
@@ -504,7 +561,7 @@ async def _do_call(self, session, tool_name: str, arguments: Dict) -> Dict:
     async def _reconnect_builtin(self, server_id: str) -> bool:
         """Tear down and reconnect a crashed builtin MCP server."""
         import sys
-        from src.builtin_mcp import _BUILTIN_SERVERS
+        from src.builtin_mcp import _BUILTIN_SERVERS, builtin_python_env
 
         if server_id not in _BUILTIN_SERVERS:
             return False
@@ -523,7 +580,7 @@ async def _reconnect_builtin(self, server_id: str) -> bool:
                 transport="stdio",
                 command=sys.executable,
                 args=[script_path],
-                env={"PYTHONPATH": base_dir},
+                env=builtin_python_env(base_dir),
             )
             if ok:
                 logger.info(f"Reconnected builtin MCP server: {name}")
diff --git a/src/mcp_oauth.py b/src/mcp_oauth.py
index 9f3b2ad4db..27a30383e5 100644
--- a/src/mcp_oauth.py
+++ b/src/mcp_oauth.py
@@ -96,7 +96,9 @@ def _load(self) -> dict:
         try:
             srv = db.query(McpServer).filter(McpServer.id == self.server_id).first()
             if srv and srv.oauth_tokens:
-                return json.loads(srv.oauth_tokens)
+                parsed = json.loads(srv.oauth_tokens)
+                if isinstance(parsed, dict):
+                    return parsed
         finally:
             db.close()
         return {}
@@ -111,6 +113,8 @@ def _update(self, key: str, value: dict) -> None:
             if srv is None:
                 return
             data = json.loads(srv.oauth_tokens) if srv.oauth_tokens else {}
+            if not isinstance(data, dict):
+                data = {}
             data[key] = value
             srv.oauth_tokens = json.dumps(data)
             db.commit()
diff --git a/src/tool_policy.py b/src/tool_policy.py
index b70b5c3be8..f0582235a3 100644
--- a/src/tool_policy.py
+++ b/src/tool_policy.py
@@ -16,6 +16,39 @@
     "output they will produce locally."
 )
 
+WEB_TOOL_NAMES = frozenset({"web_search", "web_fetch"})
+
+
+def tool_toggle_enabled(value: object) -> bool:
+    """Return true only for explicit true-like tool toggle values."""
+
+    return str(value).lower() == "true"
+
+
+def tool_toggle_explicitly_denied(value: object) -> bool:
+    """Return true when a caller explicitly supplied a non-true toggle value."""
+
+    return value is not None and not tool_toggle_enabled(value)
+
+
+def is_web_search_explicitly_denied(allow_web_search: object) -> bool:
+    """Whether the web-search agent toggle was explicitly set to false."""
+
+    return tool_toggle_explicitly_denied(allow_web_search)
+
+
+def web_search_enabled_for_turn(allow_web_search: object, use_web: object = None) -> bool:
+    """Return true only when this request explicitly enables web search.
+
+    Agent mode sends ``allow_web_search``; chat-mode pre-search sends
+    ``use_web``. If both are present, an explicit ``allow_web_search=false``
+    wins so a stale or conflicting intent path cannot re-enable web tools.
+    """
+
+    if is_web_search_explicitly_denied(allow_web_search):
+        return False
+    return tool_toggle_enabled(allow_web_search) or tool_toggle_enabled(use_web)
+
 
 _COMMON_TOOL_NAMES = {
     "api_call",
diff --git a/src/tool_utils.py b/src/tool_utils.py
index 8255bc0a96..83636cf234 100644
--- a/src/tool_utils.py
+++ b/src/tool_utils.py
@@ -9,6 +9,7 @@
 from src.constants import MAX_OUTPUT_CHARS
 
 _mcp_manager = None
+_upload_handler = None
 
 # ---------------------------------------------------------------------------
 # MCP Manager singleton
@@ -23,6 +24,21 @@ def get_mcp_manager():
     """Get the global MCP manager instance."""
     return _mcp_manager
 
+
+# ---------------------------------------------------------------------------
+# Shared upload lifecycle handler
+# ---------------------------------------------------------------------------
+
+def set_upload_handler(handler):
+    """Register the process's UploadHandler without importing app modules."""
+    global _upload_handler
+    _upload_handler = handler
+
+
+def get_upload_handler():
+    """Return the shared UploadHandler used by route and agent writers."""
+    return _upload_handler
+
 # ---------------------------------------------------------------------------
 # Helpers
 # ---------------------------------------------------------------------------
diff --git a/src/tools/calendar.py b/src/tools/calendar.py
index d442f2a42a..e6572ba40f 100644
--- a/src/tools/calendar.py
+++ b/src/tools/calendar.py
@@ -10,6 +10,8 @@
 from typing import Dict, Optional
 
 from src.tools._common import _parse_tool_args
+from src.tool_utils import get_upload_handler
+from src.upload_handler import reserve_upload_references
 
 logger = logging.getLogger(__name__)
 
@@ -408,11 +410,25 @@ def _create_calendar_reminder(summary: str, location: str, dtstart: datetime,
             importance = args.get("importance") or "normal"
             minutes_before = _reminder_minutes(args)
 
+            event_description = _event_description(args, minutes_before)
+            event_location = args.get("location", "") or ""
+            missing_id = reserve_upload_references(
+                get_upload_handler(),
+                owner,
+                event_description,
+                event_location,
+            )
+            if missing_id:
+                return {
+                    "error": f"Referenced upload is no longer available: {missing_id}",
+                    "exit_code": 1,
+                }
+
             uid = str(_uuid.uuid4())
             ev = CalendarEvent(
                 uid=uid, calendar_id=cal.id, summary=summary,
-                description=_event_description(args, minutes_before),
-                location=args.get("location", "") or "",
+                description=event_description,
+                location=event_location,
                 dtstart=dtstart, dtend=dtend, all_day=all_day,
                 is_utc=dtstart_is_utc and not all_day,
                 rrule=args.get("rrule", "") or "",
@@ -465,6 +481,17 @@ def _create_calendar_reminder(summary: str, location: str, dtstart: datetime,
             ev = _event_query().filter(CalendarEvent.uid == base_uid).first()
             if not ev:
                 return {"error": f"Event {uid} not found", "exit_code": 1}
+            missing_id = reserve_upload_references(
+                get_upload_handler(),
+                owner,
+                args.get("description"),
+                args.get("location"),
+            )
+            if missing_id:
+                return {
+                    "error": f"Referenced upload is no longer available: {missing_id}",
+                    "exit_code": 1,
+                }
             if args.get("summary") is not None:
                 ev.summary = args["summary"]
             if args.get("description") is not None:
diff --git a/src/tools/notes.py b/src/tools/notes.py
index d24be55d1d..ba980c158e 100644
--- a/src/tools/notes.py
+++ b/src/tools/notes.py
@@ -10,6 +10,8 @@
 from typing import Dict, Optional
 
 from src.tools._common import _parse_tool_args
+from src.tool_utils import get_upload_handler
+from src.upload_handler import reserve_upload_references
 
 logger = logging.getLogger(__name__)
 
@@ -198,6 +200,18 @@ def _format_note_list(notes) -> str:
                             "duplicate": True,
                             "exit_code": 0,
                         }
+            missing_id = reserve_upload_references(
+                get_upload_handler(),
+                owner,
+                content_raw,
+                args.get("color"),
+                items_json,
+            )
+            if missing_id:
+                return {
+                    "error": f"Referenced upload is no longer available: {missing_id}",
+                    "exit_code": 1,
+                }
             note = Note(
                 id=str(_uuid.uuid4()),
                 owner=owner,
@@ -235,6 +249,19 @@ def _format_note_list(notes) -> str:
                 return {"error": f"Note '{note_id}' not found", "exit_code": 1}
             if not _note_visible_to_owner(note, owner):
                 return {"error": "Note not found", "exit_code": 1}
+            missing_id = reserve_upload_references(
+                get_upload_handler(),
+                owner,
+                args.get("content"),
+                args.get("color"),
+                args.get("checklist_items"),
+                args.get("items"),
+            )
+            if missing_id:
+                return {
+                    "error": f"Referenced upload is no longer available: {missing_id}",
+                    "exit_code": 1,
+                }
             for field in ("title", "content", "note_type", "color", "label"):
                 if field in args and args[field] is not None:
                     setattr(note, field, args[field])
diff --git a/src/tools/system.py b/src/tools/system.py
index 3fedac6c37..a901992c26 100644
--- a/src/tools/system.py
+++ b/src/tools/system.py
@@ -356,7 +356,11 @@ async def do_manage_tasks(content: str, owner: Optional[str] = None) -> Dict:
             task = db.query(ScheduledTask).filter(ScheduledTask.id == task_id).first()
             if not task:
                 return {"error": f"Task {task_id} not found", "exit_code": 1}
-            if owner and task.owner and task.owner != owner:
+            # Strict ownership: the old `task.owner and task.owner != owner`
+            # skipped the check on an owner-less task (created in no-login mode
+            # or before the legacy-owner sweep), letting any authenticated user
+            # reach it. `list` already scopes to an exact owner match.
+            if owner and task.owner != owner:
                 return {"error": "Access denied", "exit_code": 1}
 
             changed = []
@@ -402,7 +406,7 @@ async def do_manage_tasks(content: str, owner: Optional[str] = None) -> Dict:
             task = db.query(ScheduledTask).filter(ScheduledTask.id == task_id).first()
             if not task:
                 return {"error": f"Task {task_id} not found", "exit_code": 1}
-            if owner and task.owner and task.owner != owner:
+            if owner and task.owner != owner:
                 return {"error": "Access denied", "exit_code": 1}
             name = task.name
             db.delete(task)
@@ -416,7 +420,7 @@ async def do_manage_tasks(content: str, owner: Optional[str] = None) -> Dict:
             task = db.query(ScheduledTask).filter(ScheduledTask.id == task_id).first()
             if not task:
                 return {"error": f"Task {task_id} not found", "exit_code": 1}
-            if owner and task.owner and task.owner != owner:
+            if owner and task.owner != owner:
                 return {"error": "Access denied", "exit_code": 1}
 
             if action == "pause":
@@ -437,7 +441,7 @@ async def do_manage_tasks(content: str, owner: Optional[str] = None) -> Dict:
             task = db.query(ScheduledTask).filter(ScheduledTask.id == task_id).first()
             if not task:
                 return {"error": f"Task {task_id} not found", "exit_code": 1}
-            if owner and task.owner and task.owner != owner:
+            if owner and task.owner != owner:
                 return {"error": "Access denied", "exit_code": 1}
 
             from src.event_bus import get_task_scheduler
diff --git a/src/upload_handler.py b/src/upload_handler.py
index 1f24c62634..ce0b4b1293 100644
--- a/src/upload_handler.py
+++ b/src/upload_handler.py
@@ -35,11 +35,34 @@ def secure_filename(filename: str) -> str:
 
 logger = logging.getLogger(__name__)
 
+
+class UploadCleanupSafetyError(RuntimeError):
+    """Raised when cleanup cannot prove that destructive work is safe."""
+
 # The extension is optional: save_upload builds the id as `{uuid.hex}{ext}`,
 # and a file with no extension (Dockerfile, README, ...) yields a bare 32-hex
 # id. Requiring `.ext` made those ids fail validation, so the stored file
 # could never be resolved or downloaded again.
 UPLOAD_ID_RE = re.compile(r"^[0-9a-fA-F]{32}(?:\.[A-Za-z0-9]+)?$")
+UPLOAD_ID_TOKEN_RE = re.compile(
+    r"(?<![0-9a-fA-F])([0-9a-fA-F]{32}(?:\.[A-Za-z0-9]+)?)(?![A-Za-z0-9])"
+)
+INTERNAL_UPLOAD_URL_RE = re.compile(
+    r"(?:odysseus://attachment/|/api/upload/)"
+    r"([0-9a-fA-F]{32}(?:\.[A-Za-z0-9]+)?)"
+    r"(?=$|[\s\"'<>\[\](){},;!?:&#]|\.(?![A-Za-z0-9]))"
+)
+PDF_SOURCE_UPLOAD_RE = re.compile(
+    r"<!--\s*pdf(?:_form)?_source\b[^>]*\bupload_id="
+    r"[\"']([0-9a-fA-F]{32}(?:\.[A-Za-z0-9]+)?)[\"'][^>]*-->",
+    re.IGNORECASE,
+)
+ATTACHMENT_REFERENCE_LINE_RE = re.compile(
+    r"\[Attachment:[^\]\r\n]*\|\s*id="
+    r"([0-9a-fA-F]{32}(?:\.[A-Za-z0-9]+)?)"
+    r"(?:\s*\||\s*\])",
+    re.IGNORECASE,
+)
 
 
 def is_valid_upload_id(upload_id: str) -> bool:
@@ -47,6 +70,110 @@ def is_valid_upload_id(upload_id: str) -> bool:
     return UPLOAD_ID_RE.fullmatch(upload_id or "") is not None
 
 
+def extract_upload_ids(value: Any) -> set[str]:
+    """Return canonical upload IDs embedded in a persisted URL/text value."""
+    if not isinstance(value, str) or not value:
+        return set()
+    return set(UPLOAD_ID_TOKEN_RE.findall(value))
+
+
+def extract_internal_upload_ids(value: Any) -> set[str]:
+    """Return IDs from explicit internal upload references only.
+
+    Cleanup intentionally uses :func:`extract_upload_ids` conservatively, but
+    write-time reservation must not treat an arbitrary 32-hex checksum in note
+    or calendar text as an upload reference. Nested JSON-like values are
+    supported because note checklist items are persisted as structured data.
+    """
+    if isinstance(value, dict):
+        found: set[str] = set()
+        for nested in value.values():
+            found.update(extract_internal_upload_ids(nested))
+        return found
+    if isinstance(value, (list, tuple, set)):
+        found: set[str] = set()
+        for nested in value:
+            found.update(extract_internal_upload_ids(nested))
+        return found
+    if not isinstance(value, str) or not value:
+        return set()
+    return (
+        set(INTERNAL_UPLOAD_URL_RE.findall(value))
+        | set(PDF_SOURCE_UPLOAD_RE.findall(value))
+        | set(ATTACHMENT_REFERENCE_LINE_RE.findall(value))
+    )
+
+
+def reserve_upload_references(
+    upload_handler: Any,
+    owner: Optional[str],
+    *values: Any,
+) -> Optional[str]:
+    """Reserve upload IDs in values before a caller persists references.
+
+    Returns the first ID that cannot be owner-checked/reserved, otherwise
+    ``None``. A missing handler is treated as no-op for backward-compatible
+    route factories; production wires the shared UploadHandler instance.
+    """
+    if upload_handler is None:
+        return None
+    upload_ids: set[str] = set()
+    for value in values:
+        upload_ids.update(extract_internal_upload_ids(value))
+    return reserve_upload_ids(upload_handler, owner, upload_ids)
+
+
+def reserve_upload_ids(
+    upload_handler: Any,
+    owner: Optional[str],
+    upload_ids: Any,
+) -> Optional[str]:
+    """Owner-reserve canonical IDs from a trusted structured reference field."""
+    if upload_handler is None:
+        return None
+    canonical_ids = {
+        str(upload_id).strip()
+        for upload_id in (upload_ids or [])
+        if is_valid_upload_id(str(upload_id).strip())
+    }
+    for upload_id in sorted(canonical_ids):
+        try:
+            resolved = upload_handler.reserve_upload(
+                upload_id,
+                owner=owner,
+                allow_admin=False,
+            )
+        except Exception:
+            resolved = None
+        if not resolved:
+            return upload_id
+    return None
+
+
+def reserve_message_upload_references(
+    upload_handler: Any,
+    owner: Optional[str],
+    content: Any,
+    metadata: Any = None,
+) -> Optional[str]:
+    """Reserve explicit chat references, including structured attachment IDs."""
+    upload_ids = extract_internal_upload_ids(content)
+    if metadata not in (None, ""):
+        if isinstance(metadata, str):
+            metadata = json.loads(metadata)
+        if not isinstance(metadata, dict):
+            raise ValueError("message metadata must be a JSON object")
+        upload_ids.update(extract_internal_upload_ids(metadata))
+        from src.attachment_refs import attachment_refs_from_metadata
+
+        upload_ids.update(
+            str(ref.get("attachment_id") or "").strip()
+            for ref in attachment_refs_from_metadata(metadata)
+            if ref.get("attachment_id")
+        )
+    return reserve_upload_ids(upload_handler, owner, upload_ids)
+
+
 def _build_upload_id(safe_filename: str) -> str:
     """Build a unique upload id whose extension matches UPLOAD_ID_RE.
 
@@ -249,43 +376,295 @@ def is_safe_file_type(self, content_type: str, filename: str) -> bool:
         
         return True
     
-    def cleanup_old_uploads(self):
-        """Remove uploaded files older than CLEANUP_DAYS days."""
+    @staticmethod
+    def _parse_upload_timestamp(value: Any) -> Optional[datetime]:
+        if not isinstance(value, str) or not value.strip():
+            return None
+        try:
+            parsed = datetime.fromisoformat(value.strip().replace("Z", "+00:00"))
+            if parsed.tzinfo is not None:
+                parsed = parsed.astimezone().replace(tzinfo=None)
+            return parsed
+        except (TypeError, ValueError):
+            return None
+
+    @classmethod
+    def _upload_metadata_is_recent(cls, info: Dict[str, Any], cutoff_date: datetime) -> bool:
+        """Return True when upload metadata records activity inside retention."""
+        for field in ("last_accessed", "created_at", "uploaded_at"):
+            parsed = cls._parse_upload_timestamp(info.get(field))
+            if parsed is None:
+                continue
+            if parsed >= cutoff_date:
+                return True
+        return False
+
+    @classmethod
+    def _upload_index_keys_for_file(
+        cls,
+        upload_index: Dict[str, Any],
+        upload_id: str,
+        file_path: str,
+    ) -> list[str]:
+        """Find a coherent set of index rows for one physical upload.
+
+        Every related row must agree on ID, canonical path, owner, and a
+        non-empty checksum. Each row must also contain the complete lifecycle
+        timestamps written for new uploads. Ambiguous or incomplete index
+        state cannot authorize destructive cleanup.
+        """
+        target_path = os.path.normcase(os.path.realpath(file_path))
+        matches: list[str] = []
+        owners: set[str] = set()
+        checksums: set[str] = set()
+        for key, info in upload_index.items():
+            if not isinstance(info, dict):
+                continue
+            stored_path = info.get("path")
+            stored_real_path = (
+                os.path.normcase(os.path.realpath(stored_path))
+                if isinstance(stored_path, str) and stored_path
+                else None
+            )
+            same_id = info.get("id") == upload_id
+            same_path = stored_real_path == target_path
+            if not same_id and not same_path:
+                continue
+            if not same_id or not same_path:
+                logger.warning(
+                    "Skipping ambiguous cleanup candidate %s: related row has id=%r path=%r",
+                    file_path,
+                    info.get("id"),
+                    stored_path,
+                )
+                return []
+
+            owner = info.get("owner")
+            if not isinstance(owner, str) or not owner.strip():
+                logger.warning(
+                    "Skipping incomplete cleanup candidate %s: matching row has no owner",
+                    file_path,
+                )
+                return []
+
+            row_checksums = {
+                str(info.get(field)).strip().lower()
+                for field in ("hash", "checksum_sha256")
+                if info.get(field) is not None and str(info.get(field)).strip()
+            }
+            if not row_checksums:
+                logger.warning(
+                    "Skipping incomplete cleanup candidate %s: matching row has no checksum",
+                    file_path,
+                )
+                return []
+            if len(row_checksums) != 1:
+                logger.warning(
+                    "Skipping ambiguous cleanup candidate %s: matching row has conflicting checksums",
+                    file_path,
+                )
+                return []
+
+            lifecycle_fields = ("uploaded_at", "created_at", "last_accessed")
+            if any(
+                cls._parse_upload_timestamp(info.get(field)) is None
+                for field in lifecycle_fields
+            ):
+                logger.warning(
+                    "Skipping incomplete cleanup candidate %s: matching row lacks lifecycle timestamps",
+                    file_path,
+                )
+                return []
+
+            matches.append(key)
+            owners.add(owner)
+            checksums.update(row_checksums)
+
+        if len(owners) > 1 or len(checksums) > 1:
+            logger.warning(
+                "Skipping ambiguous cleanup candidate %s: matching rows disagree on owner or checksum",
+                file_path,
+            )
+            return []
+        return matches
+
+    def cleanup_old_uploads(
+        self,
+        referenced_upload_ids: Optional[set[str]] = None,
+        referenced_upload_hashes: Optional[set[str]] = None,
+    ):
+        """Remove expired uploads proven unreferenced by a complete snapshot.
+
+        ``None`` means reference discovery was not completed, so cleanup fails
+        closed and removes nothing. The admin route supplies both sets after
+        scanning persisted chats, documents, and gallery records.
+        """
+        if referenced_upload_ids is None or referenced_upload_hashes is None:
+            logger.warning("Upload cleanup skipped: persisted reference snapshot unavailable")
+            return 0
+
         try:
-            cutoff_date = datetime.now() - timedelta(days=self.cleanup_days)
+            cleanup_started_at = datetime.now()
+            cutoff_date = cleanup_started_at - timedelta(days=self.cleanup_days)
             cleaned_count = 0
-            
-            for root, dirs, files in os.walk(self.upload_dir):
-                if root == self.upload_dir:
-                    continue
-                    
-                path_parts = root.split(os.sep)
-                if len(path_parts) >= 4:
+
+            referenced_ids = {str(value) for value in referenced_upload_ids}
+            referenced_hashes = {str(value) for value in referenced_upload_hashes}
+            uploads_db_path = os.path.join(self.upload_dir, "uploads.json")
+
+            # Keep index mutation and file removal serialized with upload writes.
+            # Each row removal is atomically persisted before the bytes are
+            # deleted; if deletion fails, the previous index is restored.
+            with self._index_lock:
+                current_index = dict(self._load_upload_index(fail_on_error=True))
+
+                for root, dirs, files in os.walk(self.upload_dir, followlinks=False):
+                    is_junction = getattr(os.path, "isjunction", lambda _path: False)
+                    dirs[:] = [
+                        directory
+                        for directory in dirs
+                        if not os.path.islink(os.path.join(root, directory))
+                        and not is_junction(os.path.join(root, directory))
+                    ]
+                    if root == self.upload_dir:
+                        continue
+                    if not self._inside_upload_dir(root):
+                        dirs[:] = []
+                        continue
+
+                    path_parts = root.split(os.sep)
+                    if len(path_parts) < 4:
+                        continue
                     try:
                         dir_date = datetime(int(path_parts[-3]), int(path_parts[-2]), int(path_parts[-1]))
-                        if dir_date < cutoff_date:
-                            for file in files:
-                                file_path = os.path.join(root, file)
-                                try:
-                                    os.remove(file_path)
-                                    cleaned_count += 1
-                                    logger.info(f"Cleaned up old upload: {file_path}")
-                                except Exception as e:
-                                    logger.warning(f"Failed to remove {file_path}: {e}")
-                            
-                            try:
-                                os.rmdir(root)
-                                logger.info(f"Removed empty upload directory: {root}")
-                            except Exception as e:
-                                logger.warning(f"Failed to remove directory {root}: {e}")
                     except (ValueError, IndexError):
                         continue
-            
+                    if dir_date >= cutoff_date:
+                        continue
+
+                    for file in files:
+                        # Reference discovery only understands canonical upload
+                        # IDs; unknown files fail closed instead of being swept.
+                        if not self.validate_upload_id(file):
+                            continue
+
+                        file_path = os.path.join(root, file)
+                        if not self._inside_upload_dir(file_path):
+                            logger.warning(
+                                "Skipping cleanup candidate outside upload directory: %s",
+                                file_path,
+                            )
+                            continue
+                        matching_keys = self._upload_index_keys_for_file(
+                            current_index,
+                            file,
+                            file_path,
+                        )
+                        matching_rows = [
+                            current_index[key]
+                            for key in matching_keys
+                            if isinstance(current_index.get(key), dict)
+                        ]
+
+                        # Files without authoritative live index rows are not
+                        # eligible for destructive cleanup. Reference hashes,
+                        # recency, and ownership cannot be proven for them.
+                        if not matching_rows:
+                            continue
+
+                        is_referenced = file in referenced_ids or any(
+                            str(info.get("id") or "") in referenced_ids
+                            or str(info.get("hash") or "") in referenced_hashes
+                            or str(info.get("checksum_sha256") or "") in referenced_hashes
+                            for info in matching_rows
+                        )
+                        metadata_is_recent = any(
+                            self._upload_metadata_is_recent(info, cutoff_date)
+                            for info in matching_rows
+                        )
+                        if is_referenced or metadata_is_recent:
+                            continue
+
+                        reduced_index = {
+                            key: value
+                            for key, value in current_index.items()
+                            if key not in matching_keys
+                        }
+                        if matching_keys:
+                            try:
+                                self._atomic_write_json(
+                                    uploads_db_path,
+                                    reduced_index,
+                                    sync_backup=True,
+                                )
+                            except Exception as e:
+                                try:
+                                    self._atomic_write_json(
+                                        uploads_db_path,
+                                        current_index,
+                                        sync_backup=True,
+                                    )
+                                except Exception:
+                                    logger.exception(
+                                        "Failed to restore upload indexes after reconciliation failed for %s",
+                                        file_path,
+                                    )
+                                    raise UploadCleanupSafetyError(
+                                        "upload index rollback failed before file removal"
+                                    ) from e
+                                logger.warning(
+                                    "Failed to reconcile upload index before removing %s: %s",
+                                    file_path,
+                                    e,
+                                )
+                                continue
+
+                        try:
+                            os.remove(file_path)
+                        except FileNotFoundError:
+                            # The bytes are already absent. Keep the reduced
+                            # lifecycle index instead of recreating a stale row.
+                            current_index = reduced_index
+                            logger.info(
+                                "Reconciled missing expired upload from index: %s",
+                                file_path,
+                            )
+                            continue
+                        except Exception as e:
+                            if matching_keys:
+                                try:
+                                    self._atomic_write_json(
+                                        uploads_db_path,
+                                        current_index,
+                                        sync_backup=True,
+                                    )
+                                except Exception:
+                                    logger.exception(
+                                        "Failed to restore upload index after removal failed for %s",
+                                        file_path,
+                                    )
+                                    raise UploadCleanupSafetyError(
+                                        "upload index rollback failed after file removal was refused"
+                                    ) from e
+                            logger.warning(f"Failed to remove {file_path}: {e}")
+                            continue
+
+                        current_index = reduced_index
+                        cleaned_count += 1
+                        logger.info(f"Cleaned up old unreferenced upload: {file_path}")
+
+                    try:
+                        if not os.listdir(root):
+                            os.rmdir(root)
+                            logger.info(f"Removed empty upload directory: {root}")
+                    except Exception as e:
+                        logger.warning(f"Failed to inspect/remove directory {root}: {e}")
+
             logger.info(f"Upload cleanup completed: {cleaned_count} files removed")
             return cleaned_count
         except Exception as e:
             logger.error(f"Upload cleanup failed: {e}")
-            return 0
+            raise UploadCleanupSafetyError("upload cleanup safety checks failed") from e
     
     def validate_upload_id(self, upload_id: str) -> bool:
         """Validate that the upload ID matches the expected pattern."""
@@ -293,71 +672,103 @@ def validate_upload_id(self, upload_id: str) -> bool:
 
     def _inside_upload_dir(self, path: str) -> bool:
         """Check if path is inside the upload directory."""
-        base = os.path.realpath(self.upload_dir)
-        p = os.path.realpath(path)
+        base = os.path.normcase(os.path.realpath(self.upload_dir))
+        p = os.path.normcase(os.path.realpath(path))
         try:
             return os.path.commonpath([base, p]) == base
         except Exception:
             return False
 
-    def _atomic_write_json(self, path: str, data: dict) -> None:
+    def _atomic_write_json(
+        self,
+        path: str,
+        data: dict,
+        *,
+        sync_backup: bool = False,
+    ) -> None:
         """Write `data` to `path` atomically: write to a temp file in the
         same directory, then `os.replace` onto the target. The kernel
         guarantees `os.replace` is atomic on POSIX, so a reader either
         sees the old contents or the new contents, never a half-written
-        file. Also keeps a `.bak` sibling of the previous good state.
+        file. Normally `.bak` retains the previous good state. Destructive
+        lifecycle transitions use ``sync_backup=True`` so recovery cannot
+        resurrect metadata for bytes that were deliberately removed.
         """
         directory = os.path.dirname(path) or "."
-        fd, tmp = tempfile.mkstemp(prefix=".uploads-", suffix=".tmp", dir=directory)
-        try:
-            with os.fdopen(fd, "w", encoding="utf-8") as f:
-                json.dump(data, f, indent=2)
-                f.flush()
-                os.fsync(f.fileno())
-            if os.path.exists(path):
-                bak = path + ".bak"
+
+        def _replace_json(target: str) -> None:
+            fd, tmp = tempfile.mkstemp(
+                prefix=".uploads-",
+                suffix=".tmp",
+                dir=directory,
+            )
+            try:
+                with os.fdopen(fd, "w", encoding="utf-8") as f:
+                    json.dump(data, f, indent=2)
+                    f.flush()
+                    os.fsync(f.fileno())
+                os.replace(tmp, target)
+            except Exception:
                 try:
-                    shutil.copy2(path, bak)
+                    os.unlink(tmp)
                 except OSError:
                     pass
-            os.replace(tmp, path)
-            # Update cache if this is the main index
-            if path.endswith("uploads.json"):
-                self._index_cache = data
-                try:
-                    self._index_mtime = os.path.getmtime(path)
-                except OSError:
-                    self._index_mtime = time.time()
-        except Exception:
+                raise
+
+        if sync_backup:
+            _replace_json(path + ".bak")
+        elif os.path.exists(path):
             try:
-                os.unlink(tmp)
+                shutil.copy2(path, path + ".bak")
             except OSError:
                 pass
-            raise
 
-    def _load_upload_index(self) -> Dict[str, Any]:
+        _replace_json(path)
+        # Update cache if this is the main index
+        if path.endswith("uploads.json"):
+            self._index_cache = data
+            try:
+                self._index_mtime = os.path.getmtime(path)
+            except OSError:
+                self._index_mtime = time.time()
+
+    def _load_upload_index(self, *, fail_on_error: bool = False) -> Dict[str, Any]:
         """Load the upload index from disk/cache. Uses mtime-based validation
-        to avoid redundant parsing on hot paths.
+        to avoid redundant parsing on hot paths. When ``fail_on_error`` is
+        true, a missing, malformed, or unreadable live index raises so
+        destructive callers cannot mistake corruption for an empty store.
         """
         uploads_db_path = os.path.join(self.upload_dir, "uploads.json")
-        if not os.path.exists(uploads_db_path):
+        candidates = (uploads_db_path, uploads_db_path + ".bak")
+        if fail_on_error:
+            # A backup is intentionally the previous snapshot. It is useful for
+            # non-destructive reads, but cannot authorize deletion when the live
+            # index is missing or corrupt.
+            if not os.path.exists(uploads_db_path):
+                raise ValueError("live uploads database is missing")
+            existing_candidates = [uploads_db_path]
+        else:
+            existing_candidates = [path for path in candidates if os.path.exists(path)]
+        if not existing_candidates:
             self._index_cache = {}
             self._index_mtime = 0.0
             return {}
 
         # Check cache validity
         try:
-            mtime = os.path.getmtime(uploads_db_path)
-            if self._index_cache is not None and mtime <= self._index_mtime:
+            mtime = max(os.path.getmtime(path) for path in existing_candidates)
+            if (
+                not fail_on_error
+                and self._index_cache is not None
+                and mtime <= self._index_mtime
+            ):
                 return self._index_cache
         except OSError:
             mtime = 0.0
 
         # Try the live file first, fall back to the .bak sibling if the
         # live file is truncated/corrupted.
-        for candidate in (uploads_db_path, uploads_db_path + ".bak"):
-            if not os.path.exists(candidate):
-                continue
+        for candidate in existing_candidates:
             try:
                 with open(candidate, "r", encoding="utf-8") as f:
                     data = json.load(f)
@@ -369,6 +780,8 @@ def _load_upload_index(self) -> Dict[str, Any]:
                 logger.warning(f"Failed to read uploads database ({candidate}): {e}")
                 continue
 
+        if fail_on_error:
+            raise ValueError("live uploads database is unreadable")
         self._index_cache = {}
         return {}
 
@@ -381,6 +794,144 @@ def get_upload_info(self, upload_id: str) -> Optional[Dict[str, Any]]:
                 return dict(info)
         return None
 
+    def reserve_upload(
+        self,
+        upload_id: str,
+        *,
+        owner: Optional[str],
+        auth_manager: Any = None,
+        allow_admin: bool = False,
+    ) -> Optional[Dict[str, Any]]:
+        """Owner-check and reserve an indexed upload against cleanup.
+
+        The live index lookup, ownership/path validation, and access touch all
+        occur under the cleanup lock. A durable-reference writer must not
+        commit when this returns ``None``.
+        """
+        if not self.validate_upload_id(upload_id):
+            return None
+
+        auth_configured = bool(auth_manager and getattr(auth_manager, "is_configured", False))
+        if auth_configured and not owner:
+            return None
+
+        uploads_db_path = os.path.join(self.upload_dir, "uploads.json")
+        with self._index_lock:
+            try:
+                current = dict(self._load_upload_index(fail_on_error=True))
+            except Exception:
+                logger.warning("Cannot reserve upload %s without a valid live index", upload_id)
+                return None
+            matching_keys = [
+                key
+                for key, info in current.items()
+                if isinstance(info, dict) and info.get("id") == upload_id
+            ]
+            if not matching_keys:
+                return None
+
+            matching_rows = [dict(current[key]) for key in matching_keys]
+            row_owners = {
+                str(row.get("owner")) if row.get("owner") is not None else None
+                for row in matching_rows
+            }
+            row_hashes = {
+                str(row.get("hash") or row.get("checksum_sha256"))
+                for row in matching_rows
+                if row.get("hash") or row.get("checksum_sha256")
+            }
+            if len(row_owners) != 1 or len(row_hashes) > 1:
+                logger.warning(
+                    "Cannot reserve ambiguous upload index rows for %s",
+                    upload_id,
+                )
+                return None
+
+            is_admin = False
+            if allow_admin and owner and auth_manager and hasattr(auth_manager, "is_admin"):
+                try:
+                    is_admin = bool(auth_manager.is_admin(owner))
+                except Exception:
+                    is_admin = False
+
+            now = datetime.now()
+            current_info = matching_rows[0]
+            if owner and not is_admin and current_info.get("owner") != owner:
+                return None
+            if not owner and current_info.get("owner") is not None:
+                return None
+
+            existing_paths: set[str] = set()
+            for row in matching_rows:
+                stored_path = row.get("path")
+                if not stored_path:
+                    continue
+                if not self._inside_upload_dir(stored_path):
+                    logger.warning(
+                        "Cannot reserve upload %s with an out-of-root index path",
+                        upload_id,
+                    )
+                    return None
+                if os.path.isfile(stored_path):
+                    if os.path.basename(stored_path) != upload_id:
+                        return None
+                    existing_paths.add(os.path.normcase(os.path.realpath(stored_path)))
+            if len(existing_paths) > 1:
+                logger.warning("Cannot reserve upload %s with multiple indexed paths", upload_id)
+                return None
+            path = next(iter(existing_paths), None) or self._find_upload_path(upload_id)
+            if not path or not os.path.isfile(path) or not self._inside_upload_dir(path):
+                return None
+
+            last_accessed = self._parse_upload_timestamp(current_info.get("last_accessed"))
+            path_changed = current_info.get("path") != path
+            needs_write = (
+                path_changed
+                or last_accessed is None
+                or last_accessed < now - timedelta(minutes=5)
+            )
+            if needs_write:
+                accessed_at = now.isoformat()
+                updated_index = dict(current)
+                for key in matching_keys:
+                    updated = dict(updated_index[key])
+                    updated["path"] = path
+                    updated["last_accessed"] = accessed_at
+                    updated_index[key] = updated
+                try:
+                    self._atomic_write_json(
+                        uploads_db_path,
+                        updated_index,
+                        sync_backup=True,
+                    )
+                except Exception:
+                    try:
+                        self._atomic_write_json(
+                            uploads_db_path,
+                            current,
+                            sync_backup=True,
+                        )
+                    except Exception:
+                        logger.exception(
+                            "Failed to restore upload indexes after reservation failed for %s",
+                            upload_id,
+                        )
+                    logger.exception("Failed to reserve upload %s against cleanup", upload_id)
+                    return None
+                current_info = dict(updated_index[matching_keys[0]])
+
+            resolved = dict(current_info)
+            resolved.setdefault("id", upload_id)
+            resolved["path"] = path
+            resolved.setdefault("name", os.path.basename(path))
+            resolved.setdefault("original_name", resolved["name"])
+            resolved.setdefault("mime", mimetypes.guess_type(path)[0] or "application/octet-stream")
+            if resolved.get("hash") and not resolved.get("checksum_sha256"):
+                resolved["checksum_sha256"] = resolved["hash"]
+            if resolved.get("uploaded_at") and not resolved.get("created_at"):
+                resolved["created_at"] = resolved["uploaded_at"]
+            return resolved
+
     def _renamed_upload_index_key(self, key: str, info: Dict[str, Any], old_owner: str, new_owner: str) -> str:
         """Return the storage key to use after renaming an owned upload row.
 
@@ -475,16 +1026,32 @@ def _find_upload_path(self, upload_id: str) -> Optional[str]:
         if not self.validate_upload_id(upload_id):
             return None
 
+        candidates: list[str] = []
         direct = os.path.join(self.upload_dir, upload_id)
-        if os.path.exists(direct) and self._inside_upload_dir(direct):
-            return direct
+        if os.path.isfile(direct) and self._inside_upload_dir(direct):
+            candidates.append(os.path.realpath(direct))
 
-        for root, _dirs, files in os.walk(self.upload_dir, followlinks=False):
+        for root, dirs, files in os.walk(self.upload_dir, followlinks=False):
+            is_junction = getattr(os.path, "isjunction", lambda _path: False)
+            dirs[:] = [
+                directory
+                for directory in dirs
+                if not os.path.islink(os.path.join(root, directory))
+                and not is_junction(os.path.join(root, directory))
+            ]
             if upload_id in files:
                 path = os.path.join(root, upload_id)
-                if self._inside_upload_dir(path):
-                    return path
-        return None
+                if os.path.isfile(path) and self._inside_upload_dir(path):
+                    real_path = os.path.realpath(path)
+                    if real_path not in candidates:
+                        candidates.append(real_path)
+                        if len(candidates) > 1:
+                            logger.warning(
+                                "Upload ID %s resolves to multiple physical files",
+                                upload_id,
+                            )
+                            return None
+        return candidates[0] if candidates else None
 
     def resolve_upload(
         self,
@@ -493,52 +1060,20 @@ def resolve_upload(
         auth_manager: Any = None,
         allow_admin: bool = True,
     ) -> Optional[Dict[str, Any]]:
-        """Resolve an upload ID to metadata only if the caller may read it.
+        """Resolve and reserve an upload only if the caller may read it.
 
         This is the owner-aware lookup used by internal processors. Public
         download routes already perform owner checks; chat/document paths must
-        do the same before reading file bytes server-side.
+        do the same before reading file bytes server-side. Reservation shares
+        cleanup's lifecycle lock and prevents a newly persisted reference from
+        racing final deletion.
         """
-        if not self.validate_upload_id(upload_id):
-            logger.warning(f"Invalid upload ID format: {upload_id}")
-            return None
-
-        auth_configured = bool(auth_manager and getattr(auth_manager, "is_configured", False))
-        if auth_configured and not owner:
-            return None
-
-        info = self.get_upload_info(upload_id) or {}
-        is_admin = False
-        if allow_admin and owner and auth_manager and hasattr(auth_manager, "is_admin"):
-            try:
-                is_admin = bool(auth_manager.is_admin(owner))
-            except Exception:
-                is_admin = False
-
-        if owner and not is_admin:
-            if info.get("owner") != owner:
-                logger.warning("Upload %s denied for owner %s", upload_id, owner)
-                return None
-        if not owner and info.get("owner") is not None:
-            logger.warning("Upload %s denied without an authenticated owner", upload_id)
-            return None
-
-        path = info.get("path")
-        if not path or not os.path.exists(path) or not self._inside_upload_dir(path):
-            path = self._find_upload_path(upload_id)
-        if not path:
-            return None
-        if not self._inside_upload_dir(path):
-            logger.warning(f"Upload path outside upload directory: {path}")
-            return None
-
-        resolved = dict(info)
-        resolved.setdefault("id", upload_id)
-        resolved["path"] = path
-        resolved.setdefault("name", os.path.basename(path))
-        resolved.setdefault("original_name", resolved["name"])
-        resolved.setdefault("mime", mimetypes.guess_type(path)[0] or "application/octet-stream")
-        return resolved
+        return self.reserve_upload(
+            upload_id,
+            owner=owner,
+            auth_manager=auth_manager,
+            allow_admin=allow_admin,
+        )
     
     def cleanup_rate_limits(self):
         """Remove stale entries from upload_rate_log."""
@@ -706,6 +1241,9 @@ def save_upload(self, u: UploadFile, client_ip: str, owner: str = None) -> dict:
                         # fresh-insert path below; release the lock first.
                         raise LookupError("upload entry vanished mid-dedupe")
                     existing_file["last_accessed"] = datetime.now().isoformat()
+                    existing_file.setdefault("checksum_sha256", file_hash)
+                    if existing_file.get("uploaded_at"):
+                        existing_file.setdefault("created_at", existing_file["uploaded_at"])
                     current[live_key] = existing_file
                     self._atomic_write_json(uploads_db_path, current)
                 except LookupError:
@@ -721,7 +1259,9 @@ def save_upload(self, u: UploadFile, client_ip: str, owner: str = None) -> dict:
                     "size": existing_file["size"],
                     "name": existing_file["original_name"],
                     "hash": file_hash,
+                    "checksum_sha256": existing_file.get("checksum_sha256") or file_hash,
                     "uploaded_at": existing_file["uploaded_at"],
+                    "created_at": existing_file.get("created_at") or existing_file["uploaded_at"],
                     "owner": existing_file.get("owner"),
                     "width": existing_file.get("width"),
                     "height": existing_file.get("height"),
@@ -744,6 +1284,7 @@ def save_upload(self, u: UploadFile, client_ip: str, owner: str = None) -> dict:
             raise HTTPException(status_code=500, detail=f"Failed to save file: {str(e)}")
         
         # Create file metadata
+        created_at = datetime.now().isoformat()
         file_metadata = {
             "id": file_id,
             "path": file_path,
@@ -751,9 +1292,11 @@ def save_upload(self, u: UploadFile, client_ip: str, owner: str = None) -> dict:
             "size": file_size,
             "name": safe_filename,
             "hash": file_hash,
+            "checksum_sha256": file_hash,
             "original_name": original_filename,
-            "uploaded_at": datetime.now().isoformat(),
-            "last_accessed": datetime.now().isoformat(),
+            "uploaded_at": created_at,
+            "created_at": created_at,
+            "last_accessed": created_at,
             "client_ip": client_ip,
             "owner": owner,
         }
diff --git a/static/js/MODULE_SUMMARY.md b/static/js/MODULE_SUMMARY.md
index 0e847423fa..df5b0cb33c 100644
--- a/static/js/MODULE_SUMMARY.md
+++ b/static/js/MODULE_SUMMARY.md
@@ -1,124 +1,228 @@
-# Module Organization Summary
+# Frontend Module Organization Summary
 
-## Purpose
-This document describes what each JavaScript module is responsible for.
+> **Scope:** This document describes the architecture of the Odysseus no-build
+> frontend. The app is a collection of native ES6 modules loaded from
+> `static/`. The authoritative source is the current `static/js/` tree and the
+> top-level orchestrator `static/app.js`.
 
-> **Note:** This file is a partial, historical overview — not a complete authoritative
-> inventory. The authoritative module set is the current `static/js/` tree plus the
-> scripts loaded by `static/index.html`. As of this writing that tree holds **65 `.js`
-> files** across **8 subdirectories** (`calendar/`, `color/`, `compare/`, `editor/`,
-> `emailLibrary/`, `markdown/`, `research/`, `util/`), and `static/index.html` loads
-> **35** `/static…` script tags. The catalog below covers only the original core
-> modules and is not kept in sync with every module.
+---
+
+## 1. Top-level Application Orchestrator
+
+### `static/app.js`
+*Main application entry point.*
+
+- Imports all feature modules.
+- Exposes a few modules on `window` for legacy inter-module reachability
+  (`themeModule`, `sessionModule`, `uiModule`, `adminModule`, `cookbookModule`).
+- Patches `fetch` so any `401` redirects the user to `/login`.
+- Fetches the default chat configuration and handles deep-link route openers
+  (`/notes`, `/calendar`, `/email`, `/memory`, `/gallery`, `/cookbook`, `/library`, `/tasks`).
+- Wires global event listeners: chat-history scrolling, popups, Escape handling,
+  drag-and-drop/paste attachment handling, transcription export, sidebar toggles,
+  rail/tool buttons, and session sorting.
+- Loads auth status and applies per-user privilege restrictions.
+
+### `static/index.html`
+*SPA shell.* Loads `app.js` as a module, includes the theme-aware inline script,
+and defines the DOM skeleton that the modules populate (chat history, composer,
+sidebar, icon rail, modals).
+
+---
+
+## 2. Core Foundation Modules
+
+These are imported first and used across most features.
+
+| Module | Primary Exports | Responsibility |
+|---|---|---|
+| **`ui.js`** | `showToast`, `showError`, `el`, `copyToClipboard`, `scrollHistory`, `setAutoScroll`, `autoResize`, `debounce`, `esc` | Shared UI helpers, toast notifications, scroll behavior, element accessor, text escaping. |
+| **`storage.js`** | `default` storage wrapper | LocalStorage helpers and toggle state persistence. |
+| **`markdown.js`** | `mdToHtml`, `processWithThinking`, `squashOutsideCode`, `normalizeThinkingMarkup`, `extractThinkingBlocks`, `hasUnclosedThinkTag`, `startsWithReasoningPrefix` | Markdown→HTML, thinking/reasoning block parsing, code-block normalization. |
+| **`spinner.js`** | `create`, `createWhirlpool` | Loading/spinner factories for streaming and tool cards. |
+| **`keyboard-shortcuts.js`** | `initKeyboardShortcuts` | Global keyboard shortcut wiring. |
+| **`sidebar-layout.js`** | `initSidebarLayout`, `syncRailSide` | Wide sidebar ↔ icon-rail layout behavior. |
+| **`section-management.js`** | `initSectionCollapse`, `initSectionDrag` | Collapsible/draggable sidebar sections. |
+| **`modalManager.js`** | side-effect import | Unified minimize/restore behavior for floating tool modals. |
+| **`tileManager.js`** | side-effect import | Desktop window tiling and snap-to-edge behavior. |
+| **`windowDrag.js`** | `makeWindowDraggable` | Drag support for floating panels. |
+| **`modalSnap.js`**, **`toolWindowZOrder.js`**, **`windowResize.js`** | — | Modal snapping, z-index management, resize handles. |
+
+---
+
+## 3. Chat Pipeline
+
+The largest and most central subsystem. Chat submission → backend SSE → progressive rendering of text, tools, research, documents, and UI events.
+
+| Module | Responsibility |
+|---|---|
+| **`chat.js`** | Main chat controller. Handles `handleChatSubmit`, stops/continues, builds `FormData`, posts to `/api/chat_stream`, reads the SSE stream, and dispatches each JSON event to the appropriate renderer. Tracks background streams, stalls, auto-recovery, and multi-round agent state. |
+| **`chatStream.js`** | Helpers shared between streaming consumers: browser notifications, background-stream completion toasts, and `ui_control` event handling. |
+| **`chatRenderer.js`** | Message DOM construction: `addMessage`, role labels, model route labels, color coding, footers, metrics, code blocks, sources boxes (`web`/`research`/`RAG`), findings box, images, report links, ask-user cards, welcome screen, and transcript utilities. |
+| **`streamingRenderer.js`** | Incremental streaming renderer used by `chat.js`. Freezes finalized DOM blocks and only re-renders the growing tail to avoid flicker and O(N²) re-parsing. |
+| **`streamingSegmenter.js`** | Splits a token stream into display units (text vs code fences) for `streamingRenderer.js`. |
+| **`slashCommands.js`** | Slash-command registry (`/help`, `/setup`, etc.), parsing, and dispatch handlers. Exported functions are consumed by `chat.js` and `slashAutocomplete.js`. |
+| **`slashAutocomplete.js`** | Composer autocomplete popup for `/` commands. |
+| **`composerArrowUpRecall.js`** | Recall last user message with `↑` on an empty composer. |
+| **`assistant.js`** | Assistant/persona behaviors and message styling helpers. |
+| **`tts-ai.js`** | AI text-to-speech manager, enqueueing, streaming TTS, and playback button injection. |
+| **`voiceRecorder.js`** | Voice recording from the composer microphone. |
+| **`fileHandler.js`** | Attachment picker, paste/drop handling, upload, attachment strip rendering, pending-file management. |
+| **`codeRunner.js`** | Client-side execution affordances for code blocks returned by the model. |
+
+---
+
+## 4. Model, Endpoint, and Configuration Modules
+
+| Module | Responsibility |
+|---|---|
+| **`models.js`** | Model discovery / scanning, local model port probing, provider management, model selection UI state. |
+| **`modelPicker.js`** | Composer model-picker dropdown and endpoint selection. |
+| **`modelSort.js`** | Sorting helpers for model lists. |
+| **`model/matchKey.js`** | Model-to-key matching helper. |
+| **`providers.js`** | Provider metadata and account-management helpers. |
+| **`providerDeviceFlow.js`** | OAuth device-flow support for providers. |
+| **`presets.js`** | Character/preset selection, custom preset saving, inject prefix/suffix handling. |
+| **`search.js`** | Web-search settings, provider selection, API key management. |
+| **`settings.js`** | Settings panel (models, search, appearance, users, MCP, RAG, embedding, tokens). |
+| **`admin.js`** | Admin panel and privileged user/endpoint configuration. |
+| **`theme.js`** | Theme presets, custom colors, fonts, backgrounds, live theme switching. |
+
+---
+
+## 5. Session, Sidebar, and Workspace
+
+| Module | Responsibility |
+|---|---|
+| **`sessions.js`** | Chat session list loading, creation, switching, renaming, archiving, library modal, and direct-chat creation. Tracks current session, streaming/research indicators in the sidebar. |
+| **`workspace.js`** | Workspace folder path management for shell/file tool confinement. |
+| **`search-chat.js`** | In-chat history search. |
+| **`skills.js`** | Client-side skill library UI (load, edit, delete, test, and audit status display). |
 
 ---
 
-## Core Modules (in static/js/)
-
-### 1. **ui.js**
-- UI helper functions and utilities
-- Toast notifications (`showToast`, `showError`)
-- Element getter (`el()`)
-- Clipboard operations (`copyToClipboard`)
-- Scroll management (`scrollHistory`, `setAutoScroll`)
-- Auto-resize textarea
-- Debounce utility
-
-### 2. **markdown.js**
-- Markdown processing and rendering
-- Convert markdown to HTML (`mdToHtml`)
-- Code block handling with syntax highlighting
-- Content rendering for message arrays
-- Text cleanup (`squashOutsideCode`)
-
-### 3. **sessions.js**
-- Session/chat management
-- Create, load, delete, switch sessions
-- Session history loading
-- Direct chat creation with models
-- Session renaming
-
-### 4. **memory.js**
-- AI memory management
-- Load, add, edit, delete memories
-- Memory search/filtering
-- Memory UI rendering
-- Memory count updates
-
-### 5. **fileHandler.js**
-- File attachment handling
-- File picker dialog
-- File upload to server
-- Attachment strip rendering
-- Pending files management
-- File preview/removal
-
-### 6. **voiceRecorder.js**
-- Voice recording functionality
-- Start/stop recording
-- Audio file creation
-- Microphone permission handling
-- Recording UI updates
-
-### 7. **models.js**
-- Model scanning and display
-- Local model discovery (ports 8000-8020)
-- Provider management (OpenAI)
-- Model selection UI
-
-### 8. **rag.js**
-- RAG (Retrieval Augmented Generation) management
-- Load personal documents
-- Add directories to RAG
-- Display included files/directories
-
-### 9. **presets.js**
-- Conversation preset management
-- Load, save, activate presets
-- Custom preset configuration
-- Temperature, tokens, system prompt settings
-
-### 10. **search.js**
-- Web search settings
-- Provider selection (DuckDuckGo, Brave, SearXNG)
-- API key management
-- Save/load search configuration
-
-### 11. **chat.js** ⭐ (The Big One)
-- Main chat functionality
-- Message handling (`addMessage`)
-- Chat submission (`handleChatSubmit`)
-- Streaming response handling
-- Performance metrics display
-- Abort request management
-- Loading states and error handling
+## 6. Knowledge, Memory, and RAG
+
+| Module | Responsibility |
+|---|---|
+| **`memory.js`** | AI memory CRUD, search/filter UI, memory extraction, count badge. |
+| **`rag.js`** | Personal document RAG: load documents, add directories/files, show included paths. |
+| **`group.js`** | Group-chat UI and model orchestration. |
+
+---
+
+## 7. Document and Editor Subsystems
+
+| Module | Responsibility |
+|---|---|
+| **`document.js`** | Tabbed document editor, AI edit suggestions, Markdown/HTML/CSV editing, document streaming (`streamDocOpen`/`streamDocDelta`), and panel state. |
+| **`documentLibrary.js`** | Document library modal. |
+| **`editor/`** | Gallery image editor canvas modules: layers, brush, inpaint, crop, filters, state, history panel, top-bar wiring, canvas coordinate helpers, and AI model runners for inpainting/background-removal. |
+
+---
+
+## 8. Research UI
+
+| Module | Responsibility |
+|---|---|
+| **`research/panel.js`** | Research panel UI, job list, and controls. |
+| **`research/jobs.js`** | Research job polling and status rendering. |
+| **`researchSynapse.js`** | Animated research-progress visualization shown inside the chat bubble during a research run. |
+
+---
+
+## 9. Gallery, Email, Calendar, Tasks, and Notes
+
+| Module | Responsibility |
+|---|---|
+| **`gallery.js`** / **`galleryEditor.js`** | Gallery/image library and canvas editor entry points. |
+| **`emailInbox.js`** / **`emailLibrary.js`** | Email inbox reader and library modal. Sub-modules handle signatures, reply recipients, state, and signature folding. |
+| **`calendar.js`** / **`calendar/utils.js`** / **`calendar/reminders.js`** | Calendar views, event forms, reminders. |
+| **`tasks.js`** | Scheduled task/recurring LLM job UI. |
+| **`notes.js`** | Notes and todo panel, reminders, pinboard. |
+
+---
+
+## 10. Cookbook (Model Serving)
+
+| Module | Responsibility |
+|---|---|
+| **`cookbook.js`** | Cookbook main UI: hardware fitting, presets, action panels. |
+| **`cookbook-hwfit.js`** / **`cookbook-diagnosis.js`** / **`cookbook-deps-recipes.js`** | Hardware-fit scoring, dependency diagnosis, recipe handling. |
+| **`cookbookDownload.js`** / **`cookbookServe.js`** / **`cookbookRunning.js`** / **`cookbookSchedule.js`** / **`cookbookPorts.js`** / **`cookbookProgressSignal.js`** | Model download/serve flow, running job cards, scheduling, port detection, and progress computation. |
 
 ---
 
-## Main Application File
+## 11. Compare and Utility Modules
+
+| Module | Responsibility |
+|---|---|
+| **`compare/index.js`** (with `compare/state.js`, `compare/stream.js`, `compare/panes.js`, `compare/selector.js`, `compare/scoreboard.js`, `compare/probe.js`, `compare/vote.js`, `compare/icons.js`) | Model compare mode: parallel streams, panes, scoring, vote UI. |
+| **`censor.js`** | Text/image censor overlay toggles. |
+| **`a11y.js`** | Accessibility helpers. |
+| **`platform.js`** | Platform detection (macOS/Windows/Linux) and keyboard-modifier helpers. |
+| **`escMenuStack.js`** | Stack manager for dismissible popups. |
+| **`dragSort.js`** | Drag-to-sort shared behavior. |
+| **`tourHints.js`** / **`tourAutoplay.js`** | Onboarding tour helpers. |
+| **`color/hex.js`**, **`colorPicker.js`**, **`langIcons.js`**, **`util/ordinal.js`** | Small utility modules for color, language icons, and formatting. |
+
+---
 
-### **app.js**
-- Application initialization
-- Event listener setup
-- Drag & drop handlers
-- Keyboard shortcuts
-- Module initialization
-- Global configuration (API_BASE)
-- Coordinates all modules together
+## 12. Frontend Event Streaming Flow
+
+```
+User submits composer
+  └── chat.js::handleChatSubmit() builds FormData
+        ├── fileHandler.uploadPending() for attachments
+        ├── document.js saved (if a document panel is open)
+        └── POST /api/chat_stream
+
+Server responds with SSE stream
+  └── chat.js reads chunks via res.body.getReader() + TextDecoder
+        ├── Lines starting with "event:" set next-error state
+        └── Lines starting with "data:" carry JSON payloads
+
+JSON events are dispatched by "type":
+  delta              → streamingRenderer → markdown → live reply text
+  agent_prep         → update spinner label
+  tool_start         → finalize text bubble; create agent-thread node with wave animation
+  tool_progress      → append/update live stdout/stderr tail
+  tool_output        → mark node done/failed, render output, diffs, screenshots
+  agent_step         → finalize tool thread; create new msg-continuation bubble
+  doc_stream_open    → document.js opens a live document
+  doc_stream_delta   → document.js appends content to that document
+  research_progress  → researchSynapse visualization + spinner timer
+  research_sources   → build sources box for research
+  research_done      → reload session history to show the report
+  web_sources        → build web-search sources box
+  model_info         → update role header with requested/actual model
+  fallback           → show fallback model toast + update role label
+  metrics            → collect/display token/cost metrics
+  message_saved      → store database id on the message element
+  budget_exceeded    → show budget banner
+  rounds_exhausted   → show Continue button for step-limit hits
+  teacher_takeover   → insert escalation banner, reset round state
+  skill_saved        → show skill-learned banner
+```
+
+Foreground vs background streams:
+- If the user switches sessions while a stream is running, `chat.js` pauses DOM
+  updates and stores the state in `_backgroundStreams`. Completion is signaled
+  with a sidebar dot/notifications, and the history is reloaded when the user
+  returns.
 
 ---
 
-## Dependency Order (Load Order in HTML)
-```html
-<script src="/static/js/sessions.js"></script>      <!-- 1. Sessions first -->
-<script src="/static/js/memory.js"></script>        <!-- 2. Memory -->
-<script src="/static/js/markdown.js"></script>      <!-- 3. Markdown -->
-<script src="/static/js/ui.js"></script>            <!-- 4. UI utilities -->
-<script src="/static/js/fileHandler.js"></script>   <!-- 5. File handling -->
-<script src="/static/js/voiceRecorder.js"></script> <!-- 6. Voice -->
-<script src="/static/js/models.js"></script>        <!-- 7. Models -->
-<script src="/static/js/rag.js"></script>           <!-- 8. RAG -->
-<script src="/static/js/presets.js"></script>       <!-- 9. Presets -->
-<script src="/static/js/search.js"></script>        <!-- 10. Search -->
-<script src="/static/js/chat.js"></script>          <!-- 11. Chat -->
-<script src="/static/app.js"></script>              <!-- 12. Main app LAST -->
+## 13. What Changed from the Previous Summary
+
+- The frontend is now exclusively ES6-module based; the old `<script>` tag load
+  order is no longer authoritative.
+- `chat.js` is the streaming controller, but message rendering has been split
+  into `chatRenderer.js`, `streamingRenderer.js`, `chatStream.js`, and `researchSynapse.js`.
+- New major subsystems added since the original summary: compare mode
+  (`compare/`), document editor streaming (`document.js`), research UI
+  (`research/`), model cookbook (`cookbook*.js`), group chat (`group.js`),
+  voice/TTS (`voiceRecorder.js`, `tts-ai.js`), skill UI (`skills.js`), and
+  slash autocomplete (`slashAutocomplete.js`).
+- `sessions.js` now owns sidebar session state, streaming/research indicators,
+  and the library/archive modals.
diff --git a/static/js/chat.js b/static/js/chat.js
index f9a035a8c2..06c7a1dc7a 100644
--- a/static/js/chat.js
+++ b/static/js/chat.js
@@ -1822,7 +1822,7 @@ import { wireArrowUpRecall, getLastUserMessageFromChatHistory } from './composer
                 typewriterInto(roundHolder.querySelector('.body'), errMsg);
                 break;
               }
-              if (json.delta || json.type === 'agent_prep' || json.type === 'tool_start' || json.type === 'tool_output' || json.type === 'tool_progress' || json.type === 'agent_step' || json.type === 'doc_stream_open' || json.type === 'doc_stream_delta' || json.type === 'research_progress') {
+              if (json.delta || json.type === 'agent_prep' || json.type === 'tool_start' || json.type === 'tool_output' || json.type === 'tool_progress' || json.type === 'agent_step' || json.type === 'loop_breaker_triggered' || json.type === 'intent_nudge_exhausted' || json.type === 'doc_stream_open' || json.type === 'doc_stream_delta' || json.type === 'research_progress') {
                 clearResponseTimeout();
                 clearProcessingProbe();
                 clearFirstTokenWaitTimers();
@@ -2852,6 +2852,22 @@ import { wireArrowUpRecall, getLastUserMessageFromChatHistory } from './composer
                 const chatBox = document.getElementById('chat-history');
                 chatBox.appendChild(budgetDiv);
 
+              } else if (json.type === 'loop_breaker_triggered' || json.type === 'intent_nudge_exhausted') {
+                if (_isBg) continue;
+                _cancelThinkingTimer();
+                _removeThinkingSpinner();
+                const guardDiv = document.createElement('div');
+                guardDiv.className = 'stopped-indicator';
+                const guardLabel = document.createElement('span');
+                guardLabel.textContent = `[Agent guard: ${json.message || json.reason || 'internal stop'}]`;
+                guardDiv.appendChild(guardLabel);
+                const targetBody = roundHolder && roundHolder.querySelector('.body');
+                if (targetBody) targetBody.appendChild(guardDiv);
+                else {
+                  const chatBox = document.getElementById('chat-history');
+                  if (chatBox) chatBox.appendChild(guardDiv);
+                }
+
               } else if (json.type === 'teacher_takeover') {
                 if (_isBg) continue;
                 _cancelThinkingTimer();
diff --git a/static/js/emailLibrary.js b/static/js/emailLibrary.js
index 2a6a31d9b8..d691798ec0 100644
--- a/static/js/emailLibrary.js
+++ b/static/js/emailLibrary.js
@@ -952,8 +952,20 @@ function _libCachePut(key, value) {
   }
 }
 
+function _resetBulkSelectionForContextChange({ rerender = false } = {}) {
+  const hadSelection = !!(state._selectedUids && state._selectedUids.size);
+  const wasSelectMode = !!state._selectMode;
+  if (state._selectedUids) state._selectedUids.clear();
+  state._selectMode = false;
+  if (hadSelection || wasSelectMode) {
+    _updateBulkBar();
+    if (rerender) _renderGrid();
+  }
+}
+
 function _resetEmailListForFreshLoad() {
   _exitEmailReaderModeForList();
+  _resetBulkSelectionForContextChange();
   state._libOffset = 0;
   state._libEmails = [];
   state._libTotal = 0;
@@ -2507,6 +2519,7 @@ function _clearFilterPillSideEffect() {
 
 function _addSearchPill(pill) {
   if (!pill) return;
+  _resetBulkSelectionForContextChange({ rerender: true });
   if (!Array.isArray(state._libSearchPills)) state._libSearchPills = [];
   // Dedup by email (contact), text (text pill), or filter value.
   if (pill.type === 'contact') {
@@ -2541,6 +2554,7 @@ function _searchQueryFromPills() {
 
 function _removeSearchPillAt(idx) {
   if (!Array.isArray(state._libSearchPills)) return;
+  _resetBulkSelectionForContextChange({ rerender: true });
   const removed = state._libSearchPills[idx];
   state._libSearchPills.splice(idx, 1);
   if (removed && removed.type === 'filter') _clearFilterPillSideEffect();
@@ -2718,6 +2732,7 @@ async function _initEmailSearchChipBar() {
   // directly.
   let _libSearchTypingTimer = null;
   input.addEventListener('input', async () => {
+    _resetBulkSelectionForContextChange({ rerender: true });
     state._libSearchDraft = input.value;
     await _refreshSuggestions();
     if (_libSearchTypingTimer) clearTimeout(_libSearchTypingTimer);
@@ -2853,6 +2868,7 @@ window.addEventListener('click', (e) => {
 
 async function _doSearch() {
   _exitEmailReaderModeForList();
+  _resetBulkSelectionForContextChange({ rerender: true });
   const seq = ++_libSearchSeq;
   const derived = _deriveSearchScope(state._libSearch);
   const q = derived.q;
diff --git a/static/js/keyboard-shortcuts.js b/static/js/keyboard-shortcuts.js
index 6599ed4c2f..dd7c88f2a8 100644
--- a/static/js/keyboard-shortcuts.js
+++ b/static/js/keyboard-shortcuts.js
@@ -16,7 +16,7 @@ const _defaultKeybinds = {
 };
 
 export function _matchesCombo(e, combo, isMac = IS_MAC) {
-  if (!combo) return false;
+  if (typeof combo !== 'string' || !combo) return false;
   // Drop AltGr keystrokes so typing characters on non-US layouts can't fire a
   // Ctrl+Alt shortcut — e.g. the destructive delete_session. See platform.js.
   if (isAltGrEvent(e, isMac)) return false;
diff --git a/static/js/markdown.js b/static/js/markdown.js
index 439206fcb9..8735b83e7f 100644
--- a/static/js/markdown.js
+++ b/static/js/markdown.js
@@ -661,8 +661,11 @@ export function mdToHtml(src, opts) {
         return placeholder;
       } catch (e) { return match; }
     });
-    // Inline math: $...$  (not preceded/followed by $ or digit, not spanning multiple lines)
-    s = s.replace(/(?<!\$)\$(?!\$)([^\$\n]+?)\$(?!\$)/g, (match, math) => {
+    // Inline math: $...$ — single line only, and Pandoc-style delimiter rules so
+    // currency doesn't render as math ("$5 to $10"): the opening $ must be
+    // immediately followed by a non-space, the closing $ must be immediately
+    // preceded by a non-space and not followed by a digit.
+    s = s.replace(/(?<![\$\d])\$(?!\$)(?=\S)([^\$\n]+?)(?<=\S)\$(?!\$|\d)/g, (match, math) => {
       try {
         const raw = math.replace(/&amp;/g, '&').replace(/&lt;/g, '<').replace(/&gt;/g, '>');
         const placeholder = `___MATH_BLOCK_${mathBlocks.length}___`;
diff --git a/static/style.css b/static/style.css
index 640f05d90f..1c899e479a 100644
--- a/static/style.css
+++ b/static/style.css
@@ -2070,6 +2070,9 @@ body.bg-pattern-sparkles {
       overflow-wrap: break-word;
       overflow: hidden;
     }
+    .msg-user:has(textarea) {
+      width: 85%;
+    }
     .msg-ai {
       align-items: flex-start;
       margin-right: auto;
diff --git a/tests/conftest.py b/tests/conftest.py
index e78db01cf9..2f6defa1c5 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -26,6 +26,7 @@
     import sqlalchemy  # noqa: F401
     import sqlalchemy.orm  # noqa: F401
     import core.database  # noqa: F401
+    import src.database
 except ImportError:
     pass  # not installed - the stubs below will handle it
 
diff --git a/tests/test_agent_rounds_exhausted.py b/tests/test_agent_rounds_exhausted.py
index 178faa8c1f..b792451704 100644
--- a/tests/test_agent_rounds_exhausted.py
+++ b/tests/test_agent_rounds_exhausted.py
@@ -68,3 +68,24 @@ def test_no_rounds_exhausted_on_normal_finish(monkeypatch):
     # A plain answer (no tool block) -> done-break on round 1 -> no event.
     events = _run_loop(monkeypatch, "All done, here is your answer.", max_rounds=2)
     assert not any(e.get("type") == "rounds_exhausted" for e in events), events
+
+
+def test_emits_intent_nudge_exhausted_when_cap_is_exhausted(monkeypatch):
+    _patch_common(monkeypatch)
+
+    events = _run_loop(monkeypatch, "Let me check the logs", max_rounds=5)
+
+    guard = next((e for e in events if e.get("type") == "intent_nudge_exhausted"), None)
+    assert guard is not None, events
+    assert guard["reason"] == "intent_without_action_nudge_cap"
+    assert guard["nudges"] == 2
+
+
+def test_emits_loop_breaker_triggered_when_loop_breaker_trips(monkeypatch):
+    _patch_common(monkeypatch)
+
+    events = _run_loop(monkeypatch, "```bash\necho hi\n```", max_rounds=6)
+
+    guard = next((e for e in events if e.get("type") == "loop_breaker_triggered"), None)
+    assert guard is not None, events
+    assert guard["reason"] == "loop_breaker_stall"
diff --git a/tests/test_app_db_permissions.py b/tests/test_app_db_permissions.py
new file mode 100644
index 0000000000..d6fad8d7e0
--- /dev/null
+++ b/tests/test_app_db_permissions.py
@@ -0,0 +1,268 @@
+import os
+import sys
+import subprocess
+from pathlib import Path
+
+import pytest
+
+
+@pytest.mark.skipif(
+    sys.platform == "win32",
+    reason="POSIX mode bits (0o600) don't exist on Windows; safe_chmod no-ops there.",
+)
+def test_app_db_created_with_0600(tmp_path):
+    """app.db holds secrets — it must not be world-readable.
+
+    Note: under umask 077 a fresh sqlite file is born 0600 and this would pass
+    even without the chmod; dev/CI umask is 022, where the chmod is what makes
+    it pass. No umask machinery needed — just don't read a green here as proof
+    on a 077 box.
+
+    A subprocess (not in-process patching) is used deliberately: the engine
+    binds to DATABASE_URL at import time, so a fresh interpreter with its own
+    DATABASE_URL is the clean way to exercise init_db() against a real on-disk
+    file without rebinding the already-imported engine.
+    """
+    db_file = tmp_path / "app.db"
+    env = {**os.environ, "DATABASE_URL": f"sqlite:///{db_file}"}
+    repo_root = Path(__file__).resolve().parents[1]
+    # Importing core.database runs init_db() against the temp file-backed DB.
+    # cwd=repo_root so `import core` resolves (the `-c` sys.path[0] is the CWD).
+    subprocess.run(
+        [sys.executable, "-c", "import core.database"],
+        env=env,
+        cwd=repo_root,
+        check=True,
+    )
+    assert db_file.exists()
+    mode = db_file.stat().st_mode & 0o777
+    assert mode == 0o600, f"expected 0o600, got 0o{mode:o}"
+
+    # Upgrade path: an already-deployed DB sitting at 0644 must be re-corrected
+    # on the next startup. The chmod is unconditional (not gated on create_all
+    # having created the file), so this is the common path for existing installs.
+    db_file.chmod(0o644)
+    subprocess.run(
+        [sys.executable, "-c", "import core.database"],
+        env=env,
+        cwd=repo_root,
+        check=True,
+    )
+    assert db_file.stat().st_mode & 0o777 == 0o600, "existing 0644 DB not re-locked on startup"
+
+
+def test_normalize_sqlite_url_preserves_sqlite_uri_filename():
+    """URI filenames must reach SQLAlchemy unchanged for SQLite to parse."""
+    from core.database import _normalize_sqlite_url
+
+    url = "sqlite:///file:/tmp/app.db?mode=rwc&uri=true"
+    assert _normalize_sqlite_url(url) == url
+
+
+def test_sqlite_db_path_handles_driver_and_query_forms():
+    """The path fed to chmod must come from SQLAlchemy's parsed URL, not a naive
+    replace("sqlite:///"). A driver-qualified URL (sqlite+pysqlite://) or one
+    carrying query args (?cache=shared) would otherwise resolve to the wrong
+    path and leave the real file world-readable. Pure logic — runs everywhere.
+    """
+    from sqlalchemy.engine import make_url
+
+    from core.database import _sqlite_db_path
+
+    # Plain forms (relative + absolute) resolve to the file path.
+    assert _sqlite_db_path(make_url("sqlite:///data/app.db")) == "data/app.db"
+    assert _sqlite_db_path(make_url("sqlite:////abs/app.db")) == "/abs/app.db"
+    # A driver qualifier must not defeat detection...
+    assert _sqlite_db_path(make_url("sqlite+pysqlite:///data/app.db")) == "data/app.db"
+    # ...and query args must be stripped from the path.
+    assert _sqlite_db_path(make_url("sqlite:///data/app.db?cache=shared")) == "data/app.db"
+    assert _sqlite_db_path(make_url("sqlite+pysqlite:////abs/app.db?mode=ro")) == "/abs/app.db"
+    # Nothing to lock for non-file-backed or non-sqlite databases.
+    assert _sqlite_db_path(make_url("sqlite:///:memory:")) is None
+    assert _sqlite_db_path(make_url("sqlite://")) is None
+    assert _sqlite_db_path(make_url("postgresql+psycopg2://u:p@h/db")) is None
+
+
+@pytest.mark.skipif(
+    sys.platform == "win32",
+    reason="POSIX mode bits (0o600) don't exist on Windows; safe_chmod no-ops there.",
+)
+def test_app_db_sidecars_relocked(tmp_path):
+    """Stale SQLite sidecars (-wal/-shm) left by an older 0o644 install hold
+    copies of DB pages, so startup must re-lock them too — not just app.db.
+
+    The default -journal is transient (SQLite deletes it after the create_all
+    commit), so it isn't asserted on here; -wal/-shm persist and are the real
+    exposure once WAL has ever been enabled.
+    """
+    import sqlite3
+
+    db_file = tmp_path / "app.db"
+    sqlite3.connect(db_file).close()  # a real, pre-existing DB ...
+    db_file.chmod(0o644)
+    sidecars = [tmp_path / f"app.db{sfx}" for sfx in ("-wal", "-shm")]
+    for s in sidecars:
+        s.write_bytes(b"")
+        s.chmod(0o644)
+
+    env = {**os.environ, "DATABASE_URL": f"sqlite:///{db_file}"}
+    repo_root = Path(__file__).resolve().parents[1]
+    subprocess.run(
+        [sys.executable, "-c", "import core.database"],
+        env=env,
+        cwd=repo_root,
+        check=True,
+    )
+
+    assert db_file.stat().st_mode & 0o777 == 0o600
+    for s in sidecars:
+        assert s.stat().st_mode & 0o777 == 0o600, f"{s.name} not re-locked on startup"
+
+
+def test_sqlite_db_path_handles_file_uri_forms(tmp_path):
+    """SQLite URI filenames must chmod the real filesystem path, not the
+    literal file: URI string. Memory URI databases should still be skipped."""
+    from sqlalchemy.engine import make_url
+
+    from core.database import _sqlite_db_path
+
+    db_file = tmp_path / "uri-app.db"
+
+    assert (
+        _sqlite_db_path(make_url(f"sqlite+pysqlite:///file:{db_file}?mode=rwc&uri=true"))
+        == str(db_file)
+    )
+    assert (
+        _sqlite_db_path(make_url(f"sqlite:///file:{db_file}?cache=shared&uri=true"))
+        == str(db_file)
+    )
+
+    localhost_db = tmp_path / "localhost-uri.db"
+    assert (
+        _sqlite_db_path(
+            make_url(
+                f"sqlite+pysqlite:///file://localhost{localhost_db}"
+                "?mode=rwc&uri=true"
+            )
+        )
+        == str(localhost_db)
+    )
+
+    non_uri_mode_db = tmp_path / "mode-query-file.db"
+    assert (
+        _sqlite_db_path(
+            make_url(
+                f"sqlite+pysqlite:///{non_uri_mode_db}?mode=memory"
+            )
+        )
+        == str(non_uri_mode_db)
+    )
+    assert (
+        _sqlite_db_path(make_url("sqlite+pysqlite:///file::memory:?cache=shared&uri=true"))
+        is None
+    )
+    assert (
+        _sqlite_db_path(make_url("sqlite+pysqlite:///file:memdb1?mode=memory&cache=shared&uri=true"))
+        is None
+    )
+
+
+@pytest.mark.skipif(
+    sys.platform == "win32",
+    reason="POSIX mode bits (0o600) don't exist on Windows; safe_chmod no-ops there.",
+)
+def test_app_db_file_uri_created_with_0600(tmp_path):
+    """Import-time DB initialization must lock SQLite file: URI databases too."""
+    db_file = tmp_path / "uri-app.db"
+    env = {
+        **os.environ,
+        "DATABASE_URL": f"sqlite+pysqlite:///file:{db_file}?mode=rwc&uri=true",
+    }
+    repo_root = Path(__file__).resolve().parents[1]
+
+    subprocess.run(
+        [sys.executable, "-c", "import core.database"],
+        env=env,
+        cwd=repo_root,
+        check=True,
+    )
+
+    assert db_file.exists()
+    mode = db_file.stat().st_mode & 0o777
+    assert mode == 0o600, f"expected 0o600, got 0o{mode:o}"
+
+@pytest.mark.skipif(
+    sys.platform == "win32",
+    reason="POSIX mode bits (0o600) don't exist on Windows; safe_chmod no-ops there.",
+)
+def test_app_db_localhost_file_uri_created_with_0600(tmp_path):
+    """A file://localhost URI must chmod the local path SQLite opens."""
+    db_file = tmp_path / "localhost-uri.db"
+    env = {
+        **os.environ,
+        "DATABASE_URL": (
+            f"sqlite+pysqlite:///file://localhost{db_file}"
+            "?mode=rwc&uri=true"
+        ),
+    }
+    repo_root = Path(__file__).resolve().parents[1]
+
+    subprocess.run(
+        [sys.executable, "-c", "import core.database"],
+        env=env,
+        cwd=repo_root,
+        check=True,
+    )
+
+    assert db_file.exists()
+    mode = db_file.stat().st_mode & 0o777
+    assert mode == 0o600, f"expected 0o600, got 0o{mode:o}"
+
+
+@pytest.mark.skipif(
+    sys.platform == "win32",
+    reason="POSIX mode bits (0o600) don't exist on Windows; safe_chmod no-ops there.",
+)
+def test_app_db_non_uri_mode_query_created_with_0600(tmp_path):
+    """mode=memory without uri=true must not hide a real SQLite file."""
+    db_file = tmp_path / "mode-query-file.db"
+    env = {
+        **os.environ,
+        "DATABASE_URL": f"sqlite+pysqlite:///{db_file}?mode=memory",
+    }
+    repo_root = Path(__file__).resolve().parents[1]
+
+    subprocess.run(
+        [sys.executable, "-c", "import core.database"],
+        env=env,
+        cwd=repo_root,
+        check=True,
+    )
+
+    assert db_file.exists()
+    mode = db_file.stat().st_mode & 0o777
+    assert mode == 0o600, f"expected 0o600, got 0o{mode:o}"
+
+@pytest.mark.skipif(
+    sys.platform == "win32",
+    reason="POSIX mode bits (0o600) don't exist on Windows; safe_chmod no-ops there.",
+)
+def test_app_db_plain_file_uri_created_with_0600(tmp_path):
+    """The documented sqlite:///file: URI form must remain protected."""
+    db_file = tmp_path / "plain-uri-app.db"
+    env = {
+        **os.environ,
+        "DATABASE_URL": f"sqlite:///file:{db_file}?mode=rwc&uri=true",
+    }
+    repo_root = Path(__file__).resolve().parents[1]
+
+    subprocess.run(
+        [sys.executable, "-c", "import core.database"],
+        env=env,
+        cwd=repo_root,
+        check=True,
+    )
+
+    assert db_file.exists()
+    mode = db_file.stat().st_mode & 0o777
+    assert mode == 0o600, f"expected 0o600, got 0o{mode:o}"
diff --git a/tests/test_attachment_refs.py b/tests/test_attachment_refs.py
new file mode 100644
index 0000000000..0efd161c5a
--- /dev/null
+++ b/tests/test_attachment_refs.py
@@ -0,0 +1,75 @@
+import json
+
+from src.attachment_refs import (
+    attachment_ref,
+    persistable_message_content,
+    search_index_text,
+)
+
+
+def test_persistable_message_content_replaces_inline_media_with_attachment_ref():
+    metadata = {
+        "attachments": [
+            {
+                "id": "abc123.png",
+                "name": "diagram.png",
+                "mime": "image/png",
+                "size": 42,
+                "checksum_sha256": "sha256-digest",
+                "created_at": "2026-07-09T12:00:00",
+                "vision": "A small architecture diagram.",
+            }
+        ]
+    }
+    content = [
+        {"type": "text", "text": "Please inspect this."},
+        {
+            "type": "image_url",
+            "image_url": {"url": "data:image/png;base64," + ("A" * 5000)},
+        },
+    ]
+
+    stored = persistable_message_content(content, metadata)
+
+    assert "base64" not in stored
+    assert "A" * 100 not in stored
+    assert "Please inspect this." in stored
+    assert "Attachment: diagram.png" in stored
+    assert "id=abc123.png" in stored
+    assert "sha256=sha256-digest" in stored
+    assert "A small architecture diagram." in stored
+
+
+def test_search_index_text_strips_legacy_serialized_data_url_blocks():
+    legacy = json.dumps([
+        {"type": "text", "text": "Find this useful caption"},
+        {
+            "type": "image_url",
+            "image_url": {"url": "data:image/jpeg;base64," + ("B" * 4096)},
+        },
+    ])
+
+    indexed = search_index_text(legacy)
+
+    assert indexed == "Find this useful caption\n[1 inline media payload omitted]"
+
+
+def test_attachment_ref_normalizes_hash_aliases():
+    ref = attachment_ref({
+        "id": "file-id",
+        "original_name": "report.pdf",
+        "mime": "application/pdf",
+        "size": 99,
+        "hash": "abc",
+        "uploaded_at": "2026-07-09T12:00:00",
+    })
+
+    assert ref == {
+        "type": "attachment_ref",
+        "attachment_id": "file-id",
+        "name": "report.pdf",
+        "mime": "application/pdf",
+        "size": 99,
+        "checksum_sha256": "abc",
+        "created_at": "2026-07-09T12:00:00",
+    }
diff --git a/tests/test_backup_cli_security.py b/tests/test_backup_cli_security.py
index 23baa44cb3..89d1dcddfe 100644
--- a/tests/test_backup_cli_security.py
+++ b/tests/test_backup_cli_security.py
@@ -25,6 +25,46 @@ def _verify_args(path: Path):
     return SimpleNamespace(path=str(path), pretty=False)
 
 
+def test_backup_entry_skips_files_that_disappear():
+    backup = _load_backup_cli()
+
+    class Vanished:
+        name = "gone.tar.gz"
+
+        def is_file(self):
+            return True
+
+        def stat(self):
+            raise FileNotFoundError("gone")
+
+        def __str__(self):
+            return "backups/gone.tar.gz"
+
+    assert backup._backup_entry(Vanished()) is None
+
+
+def test_backup_list_sorts_by_captured_mtime(monkeypatch):
+    backup = _load_backup_cli()
+    first = SimpleNamespace(name="older.tar.gz")
+    second = SimpleNamespace(name="newer.tar.gz")
+    monkeypatch.setattr(backup, "_BACKUP_DIR", SimpleNamespace(
+        is_dir=lambda: True,
+        iterdir=lambda: [first, second],
+    ))
+    monkeypatch.setattr(backup, "_backup_entry", lambda p: {
+        "name": p.name,
+        "modified": "2026-10-25T01:45:00" if p is first else "2026-10-25T01:15:00",
+        "_mtime": 100 if p is first else 200,
+    })
+    seen = []
+    monkeypatch.setattr(backup, "emit", lambda payload, args: seen.append(payload))
+
+    backup.cmd_list(SimpleNamespace(pretty=False))
+
+    assert [entry["name"] for entry in seen[0]] == ["newer.tar.gz", "older.tar.gz"]
+    assert all("_mtime" not in entry for entry in seen[0])
+
+
 def test_snapshot_rejects_output_inside_data_dir(tmp_path, monkeypatch):
     backup = _load_backup_cli()
     repo = tmp_path / "repo"
diff --git a/tests/test_builtin_actions_owner_scope.py b/tests/test_builtin_actions_owner_scope.py
index d14a944622..70e2e389fc 100644
--- a/tests/test_builtin_actions_owner_scope.py
+++ b/tests/test_builtin_actions_owner_scope.py
@@ -109,10 +109,9 @@ def __init__(self, owner=""):
         def select(self, *_args, **_kwargs):
             return "OK", []
 
-        def search(self, *_args, **_kwargs):
-            return "OK", [b"1 2 3"]
-
-        def fetch(self, _uid, _query):
+        def uid(self, command, *_args):
+            if command == "SEARCH":
+                return "OK", [b"1 2 3"]
             return "OK", [(None, b"From: Writer <writer@example.com>\r\n\r\n")]
 
         def logout(self):
@@ -171,11 +170,10 @@ class FakeImap:
         def select(self, *_args, **_kwargs):
             return "OK", []
 
-        def search(self, *_args, **_kwargs):
-            return "OK", [b"1 2 3"]
-
-        def fetch(self, uid, query):
-            if "HEADER.FIELDS" in query:
+        def uid(self, command, uid=None, query=None):
+            if command == "SEARCH":
+                return "OK", [b"1 2 3"]
+            if query and "HEADER.FIELDS" in query:
                 return "OK", [(None, b"From: Writer <writer@example.com>\r\n\r\n")]
             return "OK", [
                 (
diff --git a/tests/test_builtin_mcp_pythonpath.py b/tests/test_builtin_mcp_pythonpath.py
new file mode 100644
index 0000000000..9400fd35cb
--- /dev/null
+++ b/tests/test_builtin_mcp_pythonpath.py
@@ -0,0 +1,22 @@
+import os
+
+from src.builtin_mcp import builtin_python_env
+
+
+def test_builtin_python_env_preserves_existing_pythonpath(monkeypatch):
+    monkeypatch.setenv(
+        "PYTHONPATH",
+        os.pathsep.join(["/app/venv/lib/python3.13/site-packages", "/app", "/extra"]),
+    )
+
+    env = builtin_python_env("/app")
+
+    assert env == {
+        "PYTHONPATH": os.pathsep.join(["/app", "/app/venv/lib/python3.13/site-packages", "/extra"])
+    }
+
+
+def test_builtin_python_env_uses_app_root_without_existing_pythonpath(monkeypatch):
+    monkeypatch.delenv("PYTHONPATH", raising=False)
+
+    assert builtin_python_env("/srv/odysseus") == {"PYTHONPATH": "/srv/odysseus"}
diff --git a/tests/test_caldav_client_cleanup.py b/tests/test_caldav_client_cleanup.py
new file mode 100644
index 0000000000..eb91f37bc9
--- /dev/null
+++ b/tests/test_caldav_client_cleanup.py
@@ -0,0 +1,145 @@
+"""Issue #4593 — the CalDAV DAVClient must be closed on every path.
+
+`_sync_blocking` (src/caldav_sync.py) and `_writeback_blocking`
+(src/caldav_writeback.py) each open their own DAVClient. The client holds an
+HTTP session with pooled connections; if it is never closed those connections
+leak for the lifetime of the process. These tests pin that the client is
+closed on the discovery early-returns, the normal return, and the
+write-back paths, using a fake client so no network or `caldav` install is
+needed.
+"""
+
+import sys
+import types
+
+import pytest
+from unittest.mock import MagicMock
+
+
+def _stub_sync_deps(monkeypatch):
+    """Make `_sync_blocking`'s lazy imports resolve without a real caldav/db."""
+    err_mod = types.ModuleType("caldav.lib.error")
+
+    class AuthorizationError(Exception):
+        pass
+
+    class NotFoundError(Exception):
+        pass
+
+    err_mod.AuthorizationError = AuthorizationError
+    err_mod.NotFoundError = NotFoundError
+    monkeypatch.setitem(sys.modules, "caldav", types.ModuleType("caldav"))
+    monkeypatch.setitem(sys.modules, "caldav.lib", types.ModuleType("caldav.lib"))
+    monkeypatch.setitem(sys.modules, "caldav.lib.error", err_mod)
+
+    db_mod = types.ModuleType("core.database")
+    db_mod.CalendarCal = MagicMock()
+    db_mod.CalendarEvent = MagicMock()
+    db_mod.CalendarDeletedEvent = MagicMock()
+    db_mod.SessionLocal = MagicMock()
+    if "core" not in sys.modules:
+        monkeypatch.setitem(sys.modules, "core", types.ModuleType("core"))
+    monkeypatch.setitem(sys.modules, "core.database", db_mod)
+
+    # Stub routes.calendar_routes so the lazy import of _ensure_positive_duration
+    # inside _sync_blocking doesn't drag in dateutil / FastAPI / SQLAlchemy.
+    routes_mod = types.ModuleType("routes")
+    cal_routes_mod = types.ModuleType("routes.calendar_routes")
+    cal_routes_mod._ensure_positive_duration = lambda start, end, all_day: end
+    if "routes" not in sys.modules:
+        monkeypatch.setitem(sys.modules, "routes", routes_mod)
+    monkeypatch.setitem(sys.modules, "routes.calendar_routes", cal_routes_mod)
+
+    return AuthorizationError
+
+
+def test_sync_closes_client_on_discovery_auth_failure(monkeypatch):
+    import src.caldav_sync as sync
+
+    AuthorizationError = _stub_sync_deps(monkeypatch)
+    client = MagicMock()
+    client.principal.side_effect = AuthorizationError("bad credentials")
+    monkeypatch.setattr(sync, "_build_dav_client", lambda *a, **k: client)
+
+    result = sync._sync_blocking("alice", "https://dav.example.com/", "u", "p")
+
+    client.close.assert_called_once()
+    assert any("Discovery failed" in e for e in result["errors"])
+
+
+def test_sync_closes_client_when_url_fallback_fails(monkeypatch):
+    import src.caldav_sync as sync
+
+    _stub_sync_deps(monkeypatch)
+    client = MagicMock()
+    # principal() raises a generic error -> the URL-as-calendar fallback is
+    # tried; make that fail too so the function hits the early return.
+    client.principal.side_effect = RuntimeError("no principal endpoint")
+    monkeypatch.setattr(sync, "_build_dav_client", lambda *a, **k: client)
+    monkeypatch.setattr(
+        sync, "_open_url_as_calendar",
+        MagicMock(side_effect=RuntimeError("not a calendar")),
+    )
+
+    result = sync._sync_blocking("alice", "https://dav.example.com/", "u", "p")
+
+    client.close.assert_called_once()
+    assert result["errors"]
+
+
+def test_writeback_closes_client_when_no_calendars(monkeypatch):
+    import src.caldav_sync as sync
+    import src.caldav_writeback as wb
+
+    client = MagicMock()
+    monkeypatch.setattr(sync, "_build_dav_client", lambda *a, **k: client)
+    monkeypatch.setattr(wb, "_discover_calendars", lambda c: [])
+
+    result = wb._writeback_blocking(
+        "caldav-1", {"uid": "evt-1"}, False, "https://dav.example.com/", "u", "p"
+    )
+
+    client.close.assert_called_once()
+    assert result["ok"] is False
+
+
+def test_writeback_closes_client_on_success(monkeypatch):
+    import src.caldav_sync as sync
+    import src.caldav_writeback as wb
+
+    client = MagicMock()
+    monkeypatch.setattr(sync, "_build_dav_client", lambda *a, **k: client)
+    monkeypatch.setattr(wb, "_discover_calendars", lambda c: [MagicMock()])
+    monkeypatch.setattr(wb, "push_event", lambda *a, **k: {"ok": True})
+
+    result = wb._writeback_blocking(
+        "caldav-1", {"uid": "evt-1"}, False, "https://dav.example.com/", "u", "p"
+    )
+
+    client.close.assert_called_once()
+    assert result["ok"] is True
+
+
+def test_sync_closes_client_when_session_local_raises(monkeypatch):
+    import src.caldav_sync as sync
+
+    AuthorizationError = _stub_sync_deps(monkeypatch)
+
+    # Give principal() a working response so discovery passes
+    mock_principal = MagicMock()
+    mock_cal = MagicMock()
+    mock_cal.url = "https://dav.example.com/alice/home/"
+    mock_principal.calendars.return_value = [mock_cal]
+
+    client = MagicMock()
+    client.principal.return_value = mock_principal
+    monkeypatch.setattr(sync, "_build_dav_client", lambda *a, **k: client)
+
+    # Make SessionLocal blow up before any DB work
+    import sys
+    sys.modules["core.database"].SessionLocal.side_effect = RuntimeError("DB unavailable")
+
+    with pytest.raises(RuntimeError, match="DB unavailable"):
+        sync._sync_blocking("alice", "https://dav.example.com/", "u", "p")
+
+    client.close.assert_called_once()
diff --git a/tests/test_caldav_google_principal_url.py b/tests/test_caldav_google_principal_url.py
index f4eb06b0f4..3274c9dfd9 100644
--- a/tests/test_caldav_google_principal_url.py
+++ b/tests/test_caldav_google_principal_url.py
@@ -93,6 +93,10 @@ def principal(self):
     def calendar(self, url=None):
         return _FakeCalendar(url)
 
+    def close(self):
+        # Mirror the real DAVClient: sync now closes the client on every path.
+        self.closed = True
+
 
 def _install_fake_caldav(monkeypatch):
     fake = types.ModuleType("caldav")
diff --git a/tests/test_caldav_test_connection_ssl.py b/tests/test_caldav_test_connection_ssl.py
new file mode 100644
index 0000000000..0f05efc1c0
--- /dev/null
+++ b/tests/test_caldav_test_connection_ssl.py
@@ -0,0 +1,194 @@
+"""Regression: CalDAV test_connection must trust the operator's CA bundle.
+
+The pre-flight used httpx with trust_env=False, which ignored
+SSL_CERT_FILE/REQUESTS_CA_BUNDLE. Self-signed CalDAV servers that the
+real sync accepts (via caldav lib -> requests -> honors bundle) were
+rejected by the test with CERTIFICATE_VERIFY_FAILED.
+
+These tests exercise the *route handler* directly (via ASGI TestClient)
+and capture the verify= kwarg passed to httpx.AsyncClient, ensuring the
+route code — not a test-side duplicate — builds the SSL context correctly.
+"""
+import os
+import ssl
+import sys
+from unittest.mock import MagicMock, patch
+
+import httpx
+import pytest
+
+# No module-level sys.modules stubbing here: conftest pre-imports the real
+# sqlalchemy/core.database, and stubbing extras (e.g. caldav) at collection
+# time leaks MagicMocks into later tests in the same process — it made
+# test_caldav_redirect_hardening's real DAVClient a mock that never sent
+# the PROPFIND. The route's lazy imports are patched per-request instead.
+
+
+def _fake_response(status_code=207, headers=None):
+    resp = MagicMock()
+    resp.status_code = status_code
+    resp.headers = headers or {}
+    return resp
+
+
+@pytest.fixture()
+def client():
+    from fastapi import FastAPI
+    from fastapi.testclient import TestClient
+    from routes.calendar_routes import setup_calendar_routes
+
+    with patch("routes.calendar_routes._require_user", return_value="test-owner"):
+        router = setup_calendar_routes()
+    app = FastAPI()
+    app.include_router(router)
+    return TestClient(app)
+
+
+def _make_fake_async_client(captured):
+    """Return a fake httpx.AsyncClient class that captures constructor kwargs."""
+    class FakeAsyncClient:
+        def __init__(self, **kwargs):
+            captured.update(kwargs)
+
+        async def __aenter__(self):
+            return self
+
+        async def __aexit__(self, *a):
+            pass
+
+        async def request(self, *a, **kw):
+            return _fake_response(207)
+
+    return FakeAsyncClient
+
+
+def _post_test(client, captured, env=None):
+    """POST /api/calendar/test with credentials in body so no DB lookup needed.
+
+    Patches httpx.AsyncClient at the real module level so the route's
+    ``import httpx; httpx.AsyncClient(...)`` picks up the fake class.
+    Also stubs validate_caldav_url (lazy-imported from src.caldav_sync).
+    """
+    fake_cls = _make_fake_async_client(captured)
+
+    # Stub the caldav_sync module so the lazy `from src.caldav_sync import validate_caldav_url`
+    # inside the route body resolves to a pass-through.
+    caldav_sync_stub = MagicMock()
+    caldav_sync_stub.validate_caldav_url = lambda u: u
+
+    ctx_managers = [
+        patch.object(httpx, "AsyncClient", fake_cls),
+        patch.dict(sys.modules, {"src.caldav_sync": caldav_sync_stub}),
+        patch("routes.calendar_routes._require_user", return_value="test-owner"),
+    ]
+    if env is not None:
+        ctx_managers.append(patch.dict(os.environ, env))
+
+    # Enter all context managers
+    for cm in ctx_managers:
+        cm.__enter__()
+    try:
+        return client.post(
+            "/api/calendar/test",
+            json={"url": "https://cal.example.com", "username": "u", "password": "p"},
+        )
+    finally:
+        for cm in reversed(ctx_managers):
+            cm.__exit__(None, None, None)
+
+
+# ---------------------------------------------------------------------------
+# Route-level tests
+# ---------------------------------------------------------------------------
+
+def test_route_passes_ssl_context_with_correct_flags(client):
+    """The route must pass an ssl.SSLContext to httpx.AsyncClient(verify=...)
+    with trust_env=False, follow_redirects=False, and VERIFY_X509_STRICT cleared."""
+    captured = {}
+    resp = _post_test(client, captured)
+
+    assert resp.status_code == 200
+    assert isinstance(captured.get("verify"), ssl.SSLContext), (
+        f"verify= should be an ssl.SSLContext, got {type(captured.get('verify'))}"
+    )
+    assert captured.get("trust_env") is False
+    assert captured.get("follow_redirects") is False
+    ctx = captured["verify"]
+    assert not (ctx.verify_flags & ssl.VERIFY_X509_STRICT), (
+        "VERIFY_X509_STRICT must be cleared for self-signed CA compat"
+    )
+
+
+def test_route_ssl_cert_file_takes_precedence(client, tmp_path):
+    """SSL_CERT_FILE is the exact bundle loaded when both variables are set."""
+    bundle_a = tmp_path / "ssl-cert-file.pem"
+    bundle_b = tmp_path / "requests-ca-bundle.pem"
+    bundle_a.write_text("ssl-cert-file", encoding="utf-8")
+    bundle_b.write_text("requests-ca-bundle", encoding="utf-8")
+
+    loaded = []
+
+    class FakeSSLContext:
+        def __init__(self):
+            self.verify_flags = ssl.VERIFY_X509_STRICT
+
+        def load_verify_locations(self, cafile=None, capath=None, cadata=None):
+            loaded.append(
+                {
+                    "cafile": cafile,
+                    "capath": capath,
+                    "cadata": cadata,
+                }
+            )
+
+    ssl_context = FakeSSLContext()
+    captured = {}
+    env = {
+        "SSL_CERT_FILE": str(bundle_a),
+        "REQUESTS_CA_BUNDLE": str(bundle_b),
+    }
+
+    with patch.object(
+        ssl,
+        "create_default_context",
+        return_value=ssl_context,
+    ):
+        resp = _post_test(client, captured, env=env)
+
+    assert resp.status_code == 200
+    assert resp.json() == {"ok": True}
+    assert loaded == [
+        {
+            "cafile": str(bundle_a),
+            "capath": None,
+            "cadata": None,
+        }
+    ]
+    assert captured.get("verify") is ssl_context
+    assert captured.get("trust_env") is False
+    assert captured.get("follow_redirects") is False
+    assert not (
+        ssl_context.verify_flags & ssl.VERIFY_X509_STRICT
+    )
+
+
+def test_route_missing_bundle_does_not_crash(client):
+    """A nonexistent CA bundle path must not crash -- fall back to system CAs."""
+    captured = {}
+    resp = _post_test(client, captured, env={"SSL_CERT_FILE": "/nonexistent/ca-bundle.pem"})
+
+    assert resp.status_code == 200
+    ctx = captured["verify"]
+    assert isinstance(ctx, ssl.SSLContext)
+    assert not (ctx.verify_flags & ssl.VERIFY_X509_STRICT)
+
+
+def test_route_empty_env_vars_use_system_defaults(client):
+    """Empty SSL_CERT_FILE and REQUESTS_CA_BUNDLE should not crash."""
+    captured = {}
+    resp = _post_test(client, captured, env={"SSL_CERT_FILE": "", "REQUESTS_CA_BUNDLE": ""})
+
+    assert resp.status_code == 200
+    ctx = captured["verify"]
+    assert isinstance(ctx, ssl.SSLContext)
+    assert not (ctx.verify_flags & ssl.VERIFY_X509_STRICT)
diff --git a/tests/test_chat_helpers.py b/tests/test_chat_helpers.py
index 0e2cce1f75..d2d5b26731 100644
--- a/tests/test_chat_helpers.py
+++ b/tests/test_chat_helpers.py
@@ -233,6 +233,10 @@ def test_build_uploaded_file_manifest_filters_and_nulls_unreadable_paths(monkeyp
         )
 
         assert [item["id"] for item in manifest] == ["good", "outside", "missing"]
+        assert manifest[0]["type"] == "attachment_ref"
+        assert manifest[0]["attachment_id"] == "good"
+        assert manifest[0]["uri"] == "odysseus://attachment/good"
+        assert manifest[0]["read_policy"] == "owner_checked_upload"
         assert os.path.realpath(manifest[0]["path"]) == os.path.realpath(good)
         assert manifest[1]["path"] is None
         assert manifest[2]["path"] is None
diff --git a/tests/test_chat_route_tool_policy.py b/tests/test_chat_route_tool_policy.py
index a14c7805c4..ffc5cc1a2c 100644
--- a/tests/test_chat_route_tool_policy.py
+++ b/tests/test_chat_route_tool_policy.py
@@ -1,12 +1,11 @@
-"""Issue #3229 — allow_bash / allow_web_search must work for JSON API callers
-and admin users must get bash enabled by default.
+"""Issue #3229 and explicit web-toggle regressions.
 
 Bug: allow_bash and allow_web_search were only read from form_data, so JSON
 API callers (Content-Type: application/json) always had bash disabled.
 
 Fix: (1) Read from JSON body as fallback.
-     (2) Only add bash/web_search to disabled_tools when explicitly set to a
-         falsy value; when unset (None), defer to per-user privilege checks.
+     (2) Keep bash on the privilege fallback when unset.
+     (3) Require an explicit per-turn web setting before exposing web tools.
 """
 
 import ast
@@ -15,6 +14,11 @@
 import pytest
 
 from src.action_intents import classify_tool_intent
+from src.tool_policy import (
+    WEB_TOOL_NAMES,
+    is_web_search_explicitly_denied,
+    web_search_enabled_for_turn,
+)
 
 _CHAT_ROUTES = Path(__file__).resolve().parent.parent / "routes" / "chat_routes.py"
 
@@ -76,8 +80,7 @@ def test_allow_web_search_reads_from_body_as_fallback():
 
 
 def test_disabled_tools_respects_missing_vs_explicit_toggles():
-    """When allow_bash is not set (None), bash must NOT be unconditionally
-    added to disabled_tools.  The per-user privilege check handles it.
+    """Bash still defers to privileges, but web is an explicit per-turn opt-in.
     """
     source = _CHAT_ROUTES.read_text(encoding="utf-8")
 
@@ -88,11 +91,14 @@ def test_disabled_tools_respects_missing_vs_explicit_toggles():
     assert "allow_bash is not None" in source, (
         "disabled_tools check must guard against allow_bash being None"
     )
-    assert "allow_web_search is not None" in source, (
-        "disabled_tools check must guard against allow_web_search being None"
+    assert "web_search_enabled_for_turn(allow_web_search, use_web)" in source, (
+        "web tools must be gated through the explicit per-turn web setting"
+    )
+    assert "disabled_tools.update(WEB_TOOL_NAMES)" in source, (
+        "disabled_tools must add web_search/web_fetch when web is not explicitly enabled"
     )
-    assert "and not _explicit_web_intent" not in source, (
-        "explicit allow_web_search=false must not be overridden by prompt web intent"
+    assert "_forced_tools = set(WEB_TOOL_NAMES)" in source, (
+        "web tools should only be forced visible from the explicit web setting"
     )
 
 
@@ -102,9 +108,11 @@ def test_disabled_tools_respects_missing_vs_explicit_toggles():
 def _build_disabled_tools(
     allow_bash=None,
     allow_web_search=None,
+    use_web=None,
     can_use_bash=True,
     can_use_browser=True,
     explicit_web_intent=False,
+    global_disabled=None,
 ):
     """Replicate the disabled-tools logic from chat_stream for unit testing.
 
@@ -112,21 +120,36 @@ def _build_disabled_tools(
     """
     disabled_tools = set()
 
-    # Issue #3229 fix: only disable when explicitly set to a falsy value.
+    # Issue #3229 fix: only disable bash when explicitly set to a falsy value.
     if allow_bash is not None and str(allow_bash).lower() != "true":
         disabled_tools.add("bash")
-    if (
-        allow_web_search is not None
-        and str(allow_web_search).lower() != "true"
-    ):
-        disabled_tools.add("web_search")
-        disabled_tools.add("web_fetch")
+    search_enabled = web_search_enabled_for_turn(allow_web_search, use_web)
+    if is_web_search_explicitly_denied(allow_web_search) or not search_enabled:
+        disabled_tools.update(WEB_TOOL_NAMES)
+    if explicit_web_intent:
+        disabled_tools.update({
+            "bash", "python",
+            "search_chats", "manage_skills", "manage_memory",
+            "read_file", "write_file", "edit_file",
+            "create_document", "edit_document", "update_document",
+            "send_email", "reply_to_email",
+            "manage_notes", "manage_calendar", "manage_tasks",
+            "api_call", "builtin_browser",
+        })
+        if search_enabled:
+            disabled_tools.difference_update(WEB_TOOL_NAMES)
+        else:
+            disabled_tools.update(WEB_TOOL_NAMES)
+    elif search_enabled:
+        disabled_tools.difference_update(WEB_TOOL_NAMES)
 
     # Enforce per-user privileges
     if not can_use_bash:
         disabled_tools.update({"bash", "python", "read_file", "write_file"})
     if not can_use_browser:
         disabled_tools.add("builtin_browser")
+    if global_disabled and isinstance(global_disabled, list):
+        disabled_tools.update(global_disabled)
 
     return disabled_tools
 
@@ -157,6 +180,20 @@ def test_json_body_allow_web_search_false_disables_web():
     assert "web_fetch" in disabled
 
 
+def test_chat_mode_use_web_true_enables_web():
+    """Chat pre-search sends use_web=true as the explicit web setting."""
+    disabled = _build_disabled_tools(use_web="true")
+    assert "web_search" not in disabled
+    assert "web_fetch" not in disabled
+
+
+def test_allow_web_search_false_wins_over_use_web_true():
+    """The agent web toggle hard-denies web even if another path says use_web=true."""
+    disabled = _build_disabled_tools(allow_web_search="false", use_web="true")
+    assert "web_search" in disabled
+    assert "web_fetch" in disabled
+
+
 @pytest.mark.parametrize(
     "message",
     [
@@ -180,6 +217,21 @@ def test_explicit_false_disables_web_despite_prompt_web_intent(message):
     assert "web_fetch" in disabled
 
 
+def test_prompt_web_intent_does_not_enable_web_without_setting():
+    """Prompt-derived web intent alone must not expose web tools."""
+    intent = classify_tool_intent("look up the latest docs")
+    assert intent is not None
+    assert intent.category == "web"
+
+    disabled = _build_disabled_tools(
+        allow_web_search=None,
+        use_web=None,
+        explicit_web_intent=True,
+    )
+    assert "web_search" in disabled
+    assert "web_fetch" in disabled
+
+
 def test_admin_user_gets_bash_enabled_by_default():
     """When allow_bash is not set and user has can_use_bash privilege,
     bash must NOT be disabled.
@@ -188,13 +240,11 @@ def test_admin_user_gets_bash_enabled_by_default():
     assert "bash" not in disabled
 
 
-def test_admin_user_gets_web_search_enabled_by_default():
-    """When allow_web_search is not set and user has normal privileges,
-    web_search must NOT be disabled.
-    """
+def test_web_search_disabled_by_default_without_explicit_turn_setting():
+    """Missing web settings must not expose web tools by default."""
     disabled = _build_disabled_tools(allow_web_search=None)
-    assert "web_search" not in disabled
-    assert "web_fetch" not in disabled
+    assert "web_search" in disabled
+    assert "web_fetch" in disabled
 
 
 def test_non_privileged_user_without_explicit_flag_still_disabled():
@@ -213,6 +263,16 @@ def test_non_privileged_user_explicit_true_overridden_by_privilege():
     assert "bash" in disabled
 
 
+def test_global_disabled_web_wins_over_explicit_web_enable():
+    """Admin-level disabled tools are still a hard deny."""
+    disabled = _build_disabled_tools(
+        allow_web_search="true",
+        global_disabled=["web_search", "web_fetch"],
+    )
+    assert "web_search" in disabled
+    assert "web_fetch" in disabled
+
+
 def test_form_data_none_body_true_works():
     """Simulates: form_data has no allow_bash, body has allow_bash=true.
     After the fallback (`form_data.get(...) or body.get(...)`), allow_bash
diff --git a/tests/test_copilot.py b/tests/test_copilot.py
index 52d530af6f..facf9a98fa 100644
--- a/tests/test_copilot.py
+++ b/tests/test_copilot.py
@@ -89,6 +89,18 @@ def test_request_flags_vision():
     assert vision is True
 
 
+def test_request_flags_non_dict_last_message_does_not_crash():
+    # A client can send a bare-string (non-dict) last element; before the
+    # isinstance guard this raised AttributeError on last.get("role").
+    assert copilot.request_flags(["hi"]) == (False, False)
+    assert copilot.request_flags([{"role": "user"}, "trailing"]) == (False, False)
+
+
+def test_request_flags_empty_and_none():
+    assert copilot.request_flags([]) == (False, False)
+    assert copilot.request_flags(None) == (False, False)
+
+
 def test_apply_request_headers_mutates():
     h = {"X-GitHub-Api-Version": "v"}
     copilot.apply_request_headers(h, [{"role": "tool", "content": "x"}])
diff --git a/tests/test_document_processor_empty_media_subtype.py b/tests/test_document_processor_empty_media_subtype.py
new file mode 100644
index 0000000000..63737c36c3
--- /dev/null
+++ b/tests/test_document_processor_empty_media_subtype.py
@@ -0,0 +1,74 @@
+"""Regression: extensionless image/audio uploads must get a valid MIME subtype.
+
+The data-URL subtype was derived only from the stored file's extension
+(`image_format = ext[1:]`). A pasted screenshot or any file whose stored id
+carries no extension yields `ext == ""`, so the emitted URL was
+`data:image/;base64,...` — an empty MIME subtype (invalid per RFC 2046) that
+vision/audio endpoints reject, silently dropping the attachment. When the
+extension is missing, fall back to the resolved MIME subtype. Extensions that
+are present are unchanged.
+"""
+
+
+class _Handler:
+    def __init__(self, uploads, image=False, audio=False):
+        self.uploads = uploads
+        self._image = image
+        self._audio = audio
+
+    def resolve_upload(self, fid, owner=None):
+        return self.uploads.get(fid)
+
+    def _inside_upload_dir(self, path):
+        return True
+
+    def is_image_file(self, name, mime):
+        return self._image and (mime or "").startswith("image/")
+
+    def is_audio_file(self, name, mime):
+        return self._audio and (mime or "").startswith("audio/")
+
+    def is_document_file(self, name, mime):
+        return False
+
+
+def _blocks(content, block_type):
+    return [b for b in content if isinstance(b, dict) and b.get("type") == block_type]
+
+
+def test_extensionless_image_uses_mime_subtype(tmp_path):
+    import src.document_processor as dp
+
+    p = tmp_path / ("a" * 32)          # bare id, no extension
+    p.write_bytes(b"\x89PNG\r\n\x1a\nfake")
+    uploads = {"img": {"path": str(p), "name": "screenshot", "mime": "image/png"}}
+
+    content = dp.build_user_content("look", ["img"], str(tmp_path), _Handler(uploads, image=True), owner="t")
+    imgs = _blocks(content, "image_url")
+    assert imgs, content
+    assert imgs[0]["image_url"]["url"].startswith("data:image/png;base64,")
+
+
+def test_extensionless_audio_uses_mime_subtype(tmp_path):
+    import src.document_processor as dp
+
+    p = tmp_path / ("b" * 32)
+    p.write_bytes(b"fakeaudio")
+    uploads = {"aud": {"path": str(p), "name": "recording", "mime": "audio/mpeg"}}
+
+    content = dp.build_user_content("listen", ["aud"], str(tmp_path), _Handler(uploads, audio=True), owner="t")
+    auds = _blocks(content, "audio")
+    assert auds, content
+    assert auds[0]["audio"]["url"].startswith("data:audio/mpeg;base64,")
+
+
+def test_extension_present_is_unchanged(tmp_path):
+    import src.document_processor as dp
+
+    p = tmp_path / "pic.png"
+    p.write_bytes(b"\x89PNG\r\n\x1a\n")
+    uploads = {"img": {"path": str(p), "name": "pic.png", "mime": "image/png"}}
+
+    content = dp.build_user_content("look", ["img"], str(tmp_path), _Handler(uploads, image=True), owner="t")
+    imgs = _blocks(content, "image_url")
+    assert imgs[0]["image_url"]["url"].startswith("data:image/png;base64,")
diff --git a/tests/test_email_library_bulk_actions.py b/tests/test_email_library_bulk_actions.py
index 900e0a665c..4434784cc7 100644
--- a/tests/test_email_library_bulk_actions.py
+++ b/tests/test_email_library_bulk_actions.py
@@ -12,6 +12,16 @@ def _bulk_action_source() -> str:
     return text[start:end]
 
 
+def _function_source(name: str) -> str:
+    text = _EMAIL_LIBRARY.read_text(encoding="utf-8")
+    start = text.index(f"function {name}")
+    next_function = text.find("\nfunction ", start + 1)
+    next_async = text.find("\nasync function ", start + 1)
+    candidates = [idx for idx in (next_function, next_async) if idx != -1]
+    end = min(candidates) if candidates else len(text)
+    return text[start:end]
+
+
 def test_email_bulk_read_unread_calls_provider_write_routes():
     """Bulk read/unread must persist to IMAP/provider, not only mutate UI state.
 
@@ -34,3 +44,33 @@ def test_email_bulk_read_unread_checks_backend_success_before_syncing_cache():
     assert "data?.success === false" in src
     assert "throw new Error(data?.error" in src
     assert "_libCacheWriteBack()" in src
+
+
+def test_email_context_changes_clear_bulk_selection_state():
+    """IMAP UIDs are folder/account scoped, so stale bulk selections must die.
+
+    Folder, account, filter, quick-filter, attachment, and search basis changes
+    must exit select mode before the next list/search view can run bulk actions.
+    """
+    text = _EMAIL_LIBRARY.read_text(encoding="utf-8")
+    reset_src = _function_source("_resetBulkSelectionForContextChange")
+    fresh_src = _function_source("_resetEmailListForFreshLoad")
+    add_pill_src = _function_source("_addSearchPill")
+    remove_pill_src = _function_source("_removeSearchPillAt")
+    search_src = text[text.index("async function _doSearch()"):text.index("// Custom dropdown", text.index("async function _doSearch()"))]
+
+    assert "state._selectedUids.clear()" in reset_src
+    assert "state._selectMode = false" in reset_src
+    assert "_updateBulkBar()" in reset_src
+
+    assert "_resetBulkSelectionForContextChange()" in fresh_src
+    assert "_resetBulkSelectionForContextChange({ rerender: true })" in add_pill_src
+    assert "_resetBulkSelectionForContextChange({ rerender: true })" in remove_pill_src
+    assert "_resetBulkSelectionForContextChange({ rerender: true })" in search_src
+
+    assert "state._libFolder = e.target.value;" in text
+    assert "state._libFilter = e.target.value;" in text
+    assert "state._libHasAttachments = !state._libHasAttachments;" in text
+    assert "state._libAccountId = btn.dataset.accId || null;" in text
+    assert text.count("_loadEmailsFresh();") >= 5
+    assert "state._libSearchDraft = input.value;" in text
diff --git a/tests/test_email_uid_no_seqno_fallback.py b/tests/test_email_uid_no_seqno_fallback.py
new file mode 100644
index 0000000000..920505b197
--- /dev/null
+++ b/tests/test_email_uid_no_seqno_fallback.py
@@ -0,0 +1,88 @@
+"""Email move/flag must never fall back to sequence-number IMAP ops (#1874 sibling).
+
+`imaplib`'s plain `store()` / `copy()` operate on message SEQUENCE NUMBERS, not
+UIDs. `_store_email_flag` / `_move_email_message` (used by the archive / delete /
+move / mark endpoints) had an `else` fallback that, when `_uid_exists` returned
+False, ran `conn.store(uid, …)` / `conn.copy(uid, …)` + `conn.expunge()` — i.e.
+it flagged/copied whichever message occupied sequence position == the UID value
+and then permanently expunged it. A stale cached UID (or a server whose UID
+probe misbehaves) therefore deleted an unrelated email.
+
+The fix fails safe: when the UID isn't present, return False (callers surface
+"Email not found") and never touch a message by sequence number.
+
+This is distinct from #1874, which fixes the auto-spam poller's `_imap_move` in
+`routes/email_helpers.py`; this covers the user-facing endpoints in
+`routes/email_routes.py`.
+"""
+import pytest
+
+from routes import email_routes
+from routes.email_routes import _store_email_flag, _move_email_message
+
+
+class _FakeConn:
+    """Records IMAP calls. `uid_present` controls the FETCH-UID probe result.
+
+    The sequence-number commands (store/copy/expunge) raise if ever called —
+    the whole point of the fix is that they must not be reached.
+    """
+    def __init__(self, uid_present, uid_move_ok=True):
+        self.uid_present = uid_present
+        self.uid_move_ok = uid_move_ok
+        self.uid_calls = []
+        self.seqno_calls = []
+
+    def uid(self, command, *args):
+        self.uid_calls.append((command.upper(), args))
+        cmd = command.upper()
+        if cmd == "FETCH":
+            return ("OK", [b"1 (UID 5031)"] if self.uid_present else [])
+        if cmd == "MOVE":
+            return ("OK" if self.uid_move_ok else "NO", [b""])
+        if cmd in ("COPY", "STORE"):
+            return ("OK", [b""])
+        return ("OK", [b""])
+
+    # Sequence-number APIs — must never be used with a UID.
+    def store(self, *a):
+        self.seqno_calls.append(("store", a)); return ("OK", [b""])
+
+    def copy(self, *a):
+        self.seqno_calls.append(("copy", a)); return ("OK", [b""])
+
+    def expunge(self, *a):
+        self.seqno_calls.append(("expunge", a)); return ("OK", [b""])
+
+
+@pytest.fixture(autouse=True)
+def _no_folder_resolution(monkeypatch):
+    # _move_email_message resolves the destination folder via the connection;
+    # short-circuit it so the test focuses on the UID-vs-seqno behaviour.
+    monkeypatch.setattr(email_routes, "_resolve_mail_folder", lambda conn, dest, role="": dest)
+
+
+def test_store_flag_missing_uid_fails_safe():
+    conn = _FakeConn(uid_present=False)
+    assert _store_email_flag(conn, "5031", "\\Deleted", add=True) is False
+    assert conn.seqno_calls == []  # never touched a message by sequence number
+
+
+def test_move_missing_uid_fails_safe():
+    conn = _FakeConn(uid_present=False)
+    assert _move_email_message(conn, "5031", "Trash", role="trash") is False
+    assert conn.seqno_calls == []  # no copy/store/expunge on a phantom seqno
+
+
+def test_store_flag_present_uid_uses_uid_store():
+    conn = _FakeConn(uid_present=True)
+    assert _store_email_flag(conn, "5031", "\\Seen", add=True) is True
+    assert any(c[0] == "STORE" for c in conn.uid_calls)
+    assert conn.seqno_calls == []
+
+
+def test_move_present_uid_uses_uid_move():
+    conn = _FakeConn(uid_present=True, uid_move_ok=True)
+    assert _move_email_message(conn, "5031", "Archive", role="archive") is True
+    assert any(c[0] == "MOVE" for c in conn.uid_calls)
+    assert conn.seqno_calls == []
diff --git a/tests/test_hwfit_models_nonstring_fields.py b/tests/test_hwfit_models_nonstring_fields.py
new file mode 100644
index 0000000000..9bd234aca0
--- /dev/null
+++ b/tests/test_hwfit_models_nonstring_fields.py
@@ -0,0 +1,31 @@
+"""Harden hwfit model-catalog parsing against non-string field values.
+
+`params_b` and `is_prequantized` read free-form fields straight off the HF
+catalog JSON. `parameter_count` is normally a string like "7B" and
+`quantization` a string like "FP8", but a catalog row can carry a non-string
+(e.g. an integer parameter_count, or a null/number quantization). The code
+called `pc.strip()` / `q.startswith(...)` directly, so one such row raised
+AttributeError and aborted the whole ranking pass (params_b/is_prequantized
+run for every model). Non-strings are now treated as unknown.
+"""
+from services.hwfit.models import params_b, is_prequantized
+
+
+def test_params_b_nonstring_count_does_not_raise():
+    assert params_b({"parameter_count": 7}) == 0.0
+    assert params_b({"parameter_count": ["7B"]}) == 0.0
+
+
+def test_params_b_valid_count_still_parses():
+    assert params_b({"parameter_count": "7B"}) == 7.0
+    assert params_b({"parameters_raw": 7_000_000_000}) == 7.0
+
+
+def test_is_prequantized_nonstring_quantization_does_not_raise():
+    assert is_prequantized({"quantization": 8}) is False
+    assert is_prequantized({"name": "plain-model", "quantization": 123}) is False
+
+
+def test_is_prequantized_still_detects_real_markers():
+    assert is_prequantized({"name": "some-model-awq"}) is True
+    assert is_prequantized({"quantization": "FP8-Mixed"}) is True
diff --git a/tests/test_imap_uid_commands.py b/tests/test_imap_uid_commands.py
new file mode 100644
index 0000000000..bc4e9401d7
--- /dev/null
+++ b/tests/test_imap_uid_commands.py
@@ -0,0 +1,108 @@
+"""Regression: IMAP calls must use uid() not search()/fetch().
+
+conn.search() / conn.fetch() operate on volatile positional sequence
+numbers that shift whenever messages are deleted or expunged. The
+sig-learner and daily-brief actions must use conn.uid("SEARCH", ...)
+and conn.uid("FETCH", ...) which address messages by their persistent
+RFC 3501 UID (§2.3.1.1, §6.4.8).
+"""
+import pytest
+
+
+class _SpyImap:
+    """IMAP stub that records uid() calls and raises on search()/fetch()."""
+
+    def __init__(self, uid_list=b"1 2 3"):
+        self._uid_list = uid_list
+        self.uid_calls: list[tuple] = []
+
+    def select(self, *args, **kwargs):
+        return "OK", []
+
+    def uid(self, command, *args):
+        self.uid_calls.append((command,) + args)
+        if command == "SEARCH":
+            return "OK", [self._uid_list]
+        if command == "FETCH":
+            query = args[1] if len(args) > 1 else ""
+            if "HEADER.FIELDS" in query:
+                return "OK", [(None, b"From: Writer <writer@example.com>\r\n"
+                                     b"Subject: Hello\r\n\r\n")]
+            return "OK", [(None, b"Body text\r\n\r\nRegards,\r\nThe Writer\r\n")]
+        return "OK", []
+
+    def search(self, *args):
+        raise AssertionError("conn.search() called — must use conn.uid('SEARCH', ...) instead")
+
+    def fetch(self, *args):
+        raise AssertionError("conn.fetch() called — must use conn.uid('FETCH', ...) instead")
+
+    def logout(self):
+        pass
+
+
+@pytest.mark.asyncio
+async def test_sig_learner_uses_uid_search(monkeypatch):
+    """_pull_headers must call conn.uid('SEARCH', ...) not conn.search()."""
+    from routes import email_helpers
+    from src import task_endpoint
+    from src.builtin_actions import action_learn_sender_signatures
+
+    spy = _SpyImap()
+    monkeypatch.setattr(email_helpers, "_imap_connect", lambda *a, **kw: spy)
+    monkeypatch.setattr(task_endpoint, "resolve_task_candidates", lambda *a, **kw: [])
+
+    message, ok = await action_learn_sender_signatures("alice")
+
+    assert ok is False  # no LLM candidates — stops before LLM, after IMAP
+    assert any(c[0] == "SEARCH" for c in spy.uid_calls), "uid('SEARCH', ...) was not called"
+
+
+@pytest.mark.asyncio
+async def test_sig_learner_uses_uid_fetch(monkeypatch):
+    """_pull_headers must call conn.uid('FETCH', ...) not conn.fetch()."""
+    from routes import email_helpers
+    from src import task_endpoint
+    from src.builtin_actions import action_learn_sender_signatures
+
+    spy = _SpyImap()
+    monkeypatch.setattr(email_helpers, "_imap_connect", lambda *a, **kw: spy)
+    monkeypatch.setattr(task_endpoint, "resolve_task_candidates", lambda *a, **kw: [])
+
+    await action_learn_sender_signatures("alice")
+
+    assert any(c[0] == "FETCH" for c in spy.uid_calls), "uid('FETCH', ...) was not called"
+
+
+@pytest.mark.asyncio
+async def test_daily_brief_uses_uid_commands(monkeypatch):
+    """action_daily_brief email section must use uid() not search()/fetch()."""
+    from core import database
+    from core import auth as _auth_mod
+    from routes import email_helpers
+    from src.builtin_actions import action_daily_brief
+
+    class _Q:
+        def filter(self, *a, **kw): return self
+        def join(self, *a, **kw): return self
+        def order_by(self, *a): return self
+        def all(self): return []
+
+    class _Db:
+        def query(self, *a): return _Q()
+        def close(self): pass
+
+    class _FakeAuth:
+        is_configured = False
+
+    monkeypatch.setattr(database, "SessionLocal", _Db)
+    monkeypatch.setattr(_auth_mod, "AuthManager", lambda: _FakeAuth())
+
+    spy = _SpyImap(uid_list=b"10 20 30")
+    monkeypatch.setattr(email_helpers, "_imap_connect", lambda *a, **kw: spy)
+
+    message, ok = await action_daily_brief("")
+
+    assert ok is True
+    assert any(c[0] == "SEARCH" for c in spy.uid_calls), "uid('SEARCH', ...) was not called"
+    assert any(c[0] == "FETCH" for c in spy.uid_calls), "uid('FETCH', ...) was not called"
diff --git a/tests/test_kimi_code_user_agent.py b/tests/test_kimi_code_user_agent.py
index 0d9f1cb018..ed182306cd 100644
--- a/tests/test_kimi_code_user_agent.py
+++ b/tests/test_kimi_code_user_agent.py
@@ -1,4 +1,7 @@
 """Kimi Code User-Agent fallback list and 403 detection."""
+import pytest
+
+from src import llm_core
 from src.llm_core import (
     KIMI_CODE_USER_AGENTS,
     KIMI_CODE_USER_AGENT,
@@ -12,6 +15,35 @@
 )
 
 
+KIMI_CHAT_URL = "https://api.kimi.com/coding/v1/chat/completions"
+
+
+class _Resp:
+    def __init__(self, status, text="{}"):
+        self.status_code = status
+        self.content = text.encode()
+        self.text = text
+
+
+class _FakeStreamResp(_Resp):
+    async def aiter_lines(self):
+        yield "data: [DONE]"
+
+    async def aread(self):
+        return b""
+
+
+class _FakeStreamCtx:
+    def __init__(self, response):
+        self.response = response
+
+    async def __aenter__(self):
+        return self.response
+
+    async def __aexit__(self, *args):
+        return False
+
+
 class TestKimiCodeUserAgents:
     def test_default_is_first_fallback(self):
         assert KIMI_CODE_USER_AGENT == KIMI_CODE_USER_AGENTS[0]
@@ -29,9 +61,8 @@ def test_non_403_not_access_denied(self):
 
     def test_ua_candidates_prefers_cache(self):
         _kimi_code_ua_cache.clear()
-        url = "https://api.kimi.com/coding/v1/chat/completions"
-        _remember_kimi_code_user_agent(url, "Kilo-Code/1.0")
-        candidates = _kimi_code_ua_candidates(url)
+        _remember_kimi_code_user_agent(KIMI_CHAT_URL, "Kilo-Code/1.0")
+        candidates = _kimi_code_ua_candidates(KIMI_CHAT_URL)
         assert candidates[0] == "Kilo-Code/1.0"
         assert len(candidates) == len(KIMI_CODE_USER_AGENTS)
         _kimi_code_ua_cache.clear()
@@ -48,22 +79,134 @@ def test_post_retries_next_user_agent_on_403(self, monkeypatch):
         _kimi_code_ua_cache.clear()
         calls = []
 
-        class _Resp:
-            def __init__(self, status, text=""):
-                self.status_code = status
-                self.content = text.encode()
-                self.text = text
-
         def fake_post(url, headers=None, **kwargs):
             calls.append(headers.get("User-Agent"))
             if headers.get("User-Agent") == KIMI_CODE_USER_AGENTS[0]:
                 return _Resp(403, '{"error":{"type":"access_terminated_error"}}')
             return _Resp(200, "{}")
 
+        monkeypatch.setattr(llm_core.httpx, "get", lambda *a, **k: (_ for _ in ()).throw(RuntimeError()))
         monkeypatch.setattr("src.llm_core.httpx.post", fake_post)
-        url = "https://api.kimi.com/coding/v1/chat/completions"
-        r = httpx_post_kimi_aware(url, {"Authorization": "Bearer x"}, json={})
+        r = httpx_post_kimi_aware(KIMI_CHAT_URL, {"Authorization": "Bearer x"}, json={})
         assert r.status_code == 200
         assert calls[0] == KIMI_CODE_USER_AGENTS[0]
         assert calls[1] == KIMI_CODE_USER_AGENTS[1]
         _kimi_code_ua_cache.clear()
+
+    @pytest.mark.asyncio
+    async def test_async_post_uses_async_probe_not_sync_httpx_get(self, monkeypatch):
+        _kimi_code_ua_cache.clear()
+
+        class FakeClient:
+            def __init__(self):
+                self.get_user_agents = []
+                self.post_user_agents = []
+
+            async def get(self, url, headers=None, **kwargs):
+                self.get_user_agents.append(headers.get("User-Agent"))
+                if headers.get("User-Agent") == KIMI_CODE_USER_AGENTS[0]:
+                    return _Resp(403, '{"error":{"type":"access_terminated_error"}}')
+                return _Resp(200)
+
+            async def post(self, url, headers=None, **kwargs):
+                self.post_user_agents.append(headers.get("User-Agent"))
+                return _Resp(200)
+
+        def forbidden_sync_get(*args, **kwargs):
+            raise AssertionError("async Kimi path must not call sync httpx.get")
+
+        client = FakeClient()
+        monkeypatch.setattr(llm_core.httpx, "get", forbidden_sync_get)
+
+        r = await llm_core.httpx_post_kimi_aware_async(
+            client,
+            KIMI_CHAT_URL,
+            {"Authorization": "Bearer x"},
+            json={},
+        )
+
+        assert r.status_code == 200
+        assert client.get_user_agents == [KIMI_CODE_USER_AGENTS[0], KIMI_CODE_USER_AGENTS[1]]
+        assert client.post_user_agents == [KIMI_CODE_USER_AGENTS[1]]
+        assert _kimi_code_ua_cache[_kimi_code_base_key(KIMI_CHAT_URL)] == KIMI_CODE_USER_AGENTS[1]
+        _kimi_code_ua_cache.clear()
+
+    @pytest.mark.asyncio
+    async def test_async_post_preserves_fallback_when_probe_fails(self, monkeypatch):
+        _kimi_code_ua_cache.clear()
+
+        class FakeClient:
+            def __init__(self):
+                self.post_user_agents = []
+
+            async def get(self, url, headers=None, **kwargs):
+                raise RuntimeError("models probe unavailable")
+
+            async def post(self, url, headers=None, **kwargs):
+                self.post_user_agents.append(headers.get("User-Agent"))
+                if headers.get("User-Agent") == KIMI_CODE_USER_AGENTS[0]:
+                    return _Resp(403, '{"error":{"type":"access_terminated_error"}}')
+                return _Resp(200)
+
+        def forbidden_sync_get(*args, **kwargs):
+            raise AssertionError("async Kimi path must not call sync httpx.get")
+
+        client = FakeClient()
+        monkeypatch.setattr(llm_core.httpx, "get", forbidden_sync_get)
+
+        r = await llm_core.httpx_post_kimi_aware_async(
+            client,
+            KIMI_CHAT_URL,
+            {"Authorization": "Bearer x"},
+            json={},
+        )
+
+        assert r.status_code == 200
+        assert client.post_user_agents == [KIMI_CODE_USER_AGENTS[0], KIMI_CODE_USER_AGENTS[1]]
+        assert _kimi_code_ua_cache[_kimi_code_base_key(KIMI_CHAT_URL)] == KIMI_CODE_USER_AGENTS[1]
+        _kimi_code_ua_cache.clear()
+
+    @pytest.mark.asyncio
+    async def test_stream_uses_async_kimi_probe_not_sync_httpx_get(self, monkeypatch):
+        _kimi_code_ua_cache.clear()
+
+        class FakeClient:
+            def __init__(self):
+                self.get_user_agents = []
+                self.stream_headers = []
+
+            async def get(self, url, headers=None, **kwargs):
+                self.get_user_agents.append(headers.get("User-Agent"))
+                if headers.get("User-Agent") == KIMI_CODE_USER_AGENTS[0]:
+                    return _Resp(403, '{"error":{"type":"access_terminated_error"}}')
+                return _Resp(200)
+
+            def stream(self, method, url, **kwargs):
+                self.stream_headers.append(kwargs.get("headers") or {})
+                return _FakeStreamCtx(_FakeStreamResp(200))
+
+        def forbidden_sync_get(*args, **kwargs):
+            raise AssertionError("streaming Kimi path must not call sync httpx.get")
+
+        client = FakeClient()
+        monkeypatch.setattr(llm_core.httpx, "get", forbidden_sync_get)
+        monkeypatch.setattr(llm_core, "_get_http_client", lambda: client)
+        monkeypatch.setattr(llm_core, "_is_host_dead", lambda url: False)
+        monkeypatch.setattr(llm_core, "note_model_activity", lambda *args, **kwargs: None)
+        monkeypatch.setattr(llm_core, "_clear_host_dead", lambda *args, **kwargs: None)
+
+        chunks = [
+            chunk
+            async for chunk in llm_core.stream_llm(
+                KIMI_CHAT_URL,
+                "kimi-for-coding",
+                [{"role": "user", "content": "hi"}],
+                headers={"Authorization": "Bearer x"},
+            )
+        ]
+
+        assert chunks == ["data: [DONE]\n\n"]
+        assert client.get_user_agents == [KIMI_CODE_USER_AGENTS[0], KIMI_CODE_USER_AGENTS[1]]
+        assert client.stream_headers[0]["User-Agent"] == KIMI_CODE_USER_AGENTS[1]
+        assert _kimi_code_ua_cache[_kimi_code_base_key(KIMI_CHAT_URL)] == KIMI_CODE_USER_AGENTS[1]
+        _kimi_code_ua_cache.clear()
diff --git a/tests/test_manage_tasks_owner_scope.py b/tests/test_manage_tasks_owner_scope.py
new file mode 100644
index 0000000000..334698ef0b
--- /dev/null
+++ b/tests/test_manage_tasks_owner_scope.py
@@ -0,0 +1,139 @@
+"""manage_tasks mutations must fail closed on owner-less / cross-owner tasks.
+
+The edit/delete/pause/run actions of ``do_manage_tasks`` previously gated with
+``if owner and task.owner and task.owner != owner``. The middle term made the
+check a no-op whenever the task had no owner — the state a scheduled task is in
+when it was created in no-login mode (or via the localhost middleware bypass)
+before the periodic legacy-owner sweep reassigns it to the admin user. So any
+authenticated user's agent could edit, delete, pause, or *run* another tenant's
+owner-less task. The sibling ``list`` action already scopes with an exact
+``ScheduledTask.owner == owner`` filter, so the mutators were strictly more
+permissive than the reader.
+"""
+
+import json
+import tempfile
+
+import pytest
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+from sqlalchemy.pool import NullPool
+
+from tests.helpers.import_state import clear_fake_database_modules
+
+clear_fake_database_modules()
+
+import core.database as cdb
+from core.database import ScheduledTask
+from src.tools.system import do_manage_tasks
+
+_TMPDB = tempfile.NamedTemporaryFile(suffix=".db", delete=False)
+_ENGINE = create_engine(
+    f"sqlite:///{_TMPDB.name}",
+    connect_args={"check_same_thread": False},
+    poolclass=NullPool,
+)
+cdb.Base.metadata.create_all(_ENGINE)
+_TS = sessionmaker(bind=_ENGINE, autoflush=False, autocommit=False)
+# do_manage_tasks does `from core.database import SessionLocal` at call time,
+# so patching the module attribute is enough to point it at the temp DB.
+cdb.SessionLocal = _TS
+
+
+def _seed(task_id, owner):
+    db = _TS()
+    try:
+        db.add(ScheduledTask(
+            id=task_id, owner=owner, name=task_id, prompt="original",
+            task_type="llm", trigger_type="webhook", status="active",
+            output_target="session",
+        ))
+        db.commit()
+    finally:
+        db.close()
+
+
+def _get(task_id):
+    db = _TS()
+    try:
+        return db.query(ScheduledTask).filter(ScheduledTask.id == task_id).first()
+    finally:
+        db.close()
+
+
+@pytest.mark.asyncio
+async def test_edit_denied_on_ownerless_task_for_authenticated_user():
+    _seed("ownerless-edit", None)
+    out = await do_manage_tasks(
+        json.dumps({"action": "edit", "task_id": "ownerless-edit", "prompt": "pwned"}),
+        owner="alice",
+    )
+    assert out["exit_code"] == 1 and out["error"] == "Access denied"
+    assert _get("ownerless-edit").prompt == "original"
+
+
+@pytest.mark.asyncio
+async def test_delete_denied_on_ownerless_task_for_authenticated_user():
+    _seed("ownerless-del", None)
+    out = await do_manage_tasks(
+        json.dumps({"action": "delete", "task_id": "ownerless-del"}),
+        owner="alice",
+    )
+    assert out["exit_code"] == 1 and out["error"] == "Access denied"
+    assert _get("ownerless-del") is not None
+
+
+@pytest.mark.asyncio
+async def test_pause_denied_on_ownerless_task_for_authenticated_user():
+    _seed("ownerless-pause", None)
+    out = await do_manage_tasks(
+        json.dumps({"action": "pause", "task_id": "ownerless-pause"}),
+        owner="alice",
+    )
+    assert out["exit_code"] == 1 and out["error"] == "Access denied"
+    assert _get("ownerless-pause").status == "active"
+
+
+@pytest.mark.asyncio
+async def test_run_denied_on_ownerless_task_for_authenticated_user():
+    _seed("ownerless-run", None)
+    out = await do_manage_tasks(
+        json.dumps({"action": "run", "task_id": "ownerless-run"}),
+        owner="alice",
+    )
+    assert out["exit_code"] == 1 and out["error"] == "Access denied"
+
+
+@pytest.mark.asyncio
+async def test_edit_denied_on_other_owners_task():
+    _seed("bob-task", "bob")
+    out = await do_manage_tasks(
+        json.dumps({"action": "edit", "task_id": "bob-task", "prompt": "pwned"}),
+        owner="alice",
+    )
+    assert out["exit_code"] == 1 and out["error"] == "Access denied"
+    assert _get("bob-task").prompt == "original"
+
+
+@pytest.mark.asyncio
+async def test_edit_allowed_for_matching_owner():
+    _seed("alice-task", "alice")
+    out = await do_manage_tasks(
+        json.dumps({"action": "edit", "task_id": "alice-task", "prompt": "updated"}),
+        owner="alice",
+    )
+    assert out["exit_code"] == 0
+    assert _get("alice-task").prompt == "updated"
+
+
+@pytest.mark.asyncio
+async def test_edit_allowed_in_no_login_mode():
+    # owner is None when auth is disabled — single-user mode keeps full access
+    # to shared (owner-less) tasks, exactly as `list` returns them unfiltered.
+    _seed("shared-task", None)
+    out = await do_manage_tasks(
+        json.dumps({"action": "edit", "task_id": "shared-task", "prompt": "updated"}),
+        owner=None,
+    )
+    assert out["exit_code"] == 0
+    assert _get("shared-task").prompt == "updated"
diff --git a/tests/test_markdown_rendering_js.py b/tests/test_markdown_rendering_js.py
index e0f493effa..2ffe8914f7 100644
--- a/tests/test_markdown_rendering_js.py
+++ b/tests/test_markdown_rendering_js.py
@@ -18,12 +18,24 @@ def node_available():
         pytest.skip("node binary not on PATH")
 
 
-def _run_markdown_case(markdown: str, render_expr: str = "mod.mdToHtml(input)"):
+def _run_markdown_case(markdown: str, render_expr: str = "mod.mdToHtml(input)", with_katex: bool = False):
     script = textwrap.dedent(
         r"""
         import fs from 'node:fs';
 
         globalThis.window = { location: { origin: 'http://localhost' }, katex: null };
+        if (__WITH_KATEX__) {
+          // Minimal stand-in for the CDN katex global: wraps the source so tests
+          // can assert what was (or wasn't) handed to KaTeX.
+          const katexStub = {
+            renderToString(src, opts) {
+              const display = !!(opts && opts.displayMode);
+              return `<span class="katex" data-display="${display}">${src}</span>`;
+            },
+          };
+          globalThis.window.katex = katexStub;
+          globalThis.katex = katexStub;
+        }
         globalThis.document = {
           readyState: 'loading',
           addEventListener() {},
@@ -77,7 +89,9 @@ def _run_markdown_case(markdown: str, render_expr: str = "mod.mdToHtml(input)"):
         const input = JSON.parse(process.argv[1]);
         console.log(JSON.stringify({ html: __RENDER_EXPR__ }));
         """
-    ).replace("__RENDER_EXPR__", render_expr)
+    ).replace("__RENDER_EXPR__", render_expr).replace(
+        "__WITH_KATEX__", "true" if with_katex else "false"
+    )
     result = subprocess.run(
         ["node", "--input-type=module", "-e", script, json.dumps(markdown)],
         cwd=_REPO,
@@ -200,6 +214,33 @@ def test_inline_code_content_is_html_escaped(node_available):
     assert "<b>" not in html
 
 
+def test_currency_dollar_amounts_are_not_rendered_as_math(node_available):
+    # "$5 to $10" used to pair the two dollar signs as inline-math delimiters
+    # and render "5 to" through KaTeX. Pandoc-style rules now reject it: the
+    # closing $ is preceded by a space and followed by a digit.
+    html = _run_markdown_case(
+        "The price rose from $5 to $10 overnight.", with_katex=True
+    )
+
+    assert 'class="katex"' not in html
+    assert "$5" in html
+    assert "$10" in html
+
+
+def test_inline_math_still_renders_through_katex(node_available):
+    html = _run_markdown_case("Pythagoras: $x^2 + y^2 = z^2$ holds.", with_katex=True)
+
+    assert '<span class="katex" data-display="false">x^2 + y^2 = z^2</span>' in html
+    assert "$" not in html
+
+
+def test_display_math_still_renders_through_katex(node_available):
+    html = _run_markdown_case("$$\\frac{a}{b}$$", with_katex=True)
+
+    assert 'data-display="true"' in html
+    assert "$$" not in html
+
+
 def test_dotted_python_import_paths_are_not_autolinked(node_available):
     html = _run_markdown_case(
         "from imblearn.combine import SMOTETomek\n"
diff --git a/tests/test_matchescombo_nonstring_js.py b/tests/test_matchescombo_nonstring_js.py
new file mode 100644
index 0000000000..ea3b22e71c
--- /dev/null
+++ b/tests/test_matchescombo_nonstring_js.py
@@ -0,0 +1,47 @@
+"""Pin _matchesCombo (static/js/keyboard-shortcuts.js) against a non-string
+keybind. Driven through `node --input-type=module` (same approach as
+tests/test_markdown_table_row_js.py); skips when `node` is missing.
+
+Regression: keybinds are merged from the server response of
+`/api/auth/settings` (`{ ..._defaultKeybinds, ...s.keybinds }`). A corrupt
+or malformed `keybinds` value (e.g. a number instead of "ctrl+k") reached
+`combo.split('+')` and threw "combo.split is not a function", breaking the
+whole keydown handler. The guard treats any non-string combo as "no match".
+"""
+import json
+import shutil
+import subprocess
+from pathlib import Path
+
+import pytest
+
+_REPO = Path(__file__).resolve().parent.parent
+_MOD = _REPO / "static" / "js" / "keyboard-shortcuts.js"
+_HAS_NODE = shutil.which("node") is not None
+
+_EVENT = "{key:'k',ctrlKey:false,altKey:false,shiftKey:false,metaKey:false}"
+
+
+def _match(combo_js):
+    js = f"""
+    import {{ _matchesCombo }} from '{_MOD.as_posix()}';
+    console.log(JSON.stringify(_matchesCombo({_EVENT}, {combo_js})));
+    """
+    proc = subprocess.run(
+        ["node", "--input-type=module"],
+        input=js, capture_output=True, text=True, cwd=str(_REPO), timeout=30,
+    )
+    assert proc.returncode == 0, proc.stderr
+    return json.loads(proc.stdout.strip())
+
+
+@pytest.mark.skipif(not _HAS_NODE, reason="node binary not on PATH")
+def test_non_string_combo_is_no_match():
+    assert _match("123") is False
+    assert _match("{}") is False
+    assert _match("null") is False
+
+
+@pytest.mark.skipif(not _HAS_NODE, reason="node binary not on PATH")
+def test_matching_combo_still_fires():
+    assert _match("'k'") is True
diff --git a/tests/test_mcp_oauth.py b/tests/test_mcp_oauth.py
index a9f5fdf6ba..6fb6f43b9e 100644
--- a/tests/test_mcp_oauth.py
+++ b/tests/test_mcp_oauth.py
@@ -1,4 +1,5 @@
 import asyncio
+import json
 from src import mcp_oauth
 
 
@@ -79,3 +80,53 @@ async def go():
     t = asyncio.run(go())
     assert t.access_token == "abc"
     assert srv.oauth_tokens is not None  # persisted as JSON
+
+
+def _fake_storage(oauth_tokens):
+    class FakeSrv:
+        pass
+
+    srv = FakeSrv()
+    srv.oauth_tokens = oauth_tokens
+
+    class FakeQuery:
+        def filter(self, *a):
+            return self
+
+        def first(self):
+            return srv
+
+    class FakeSession:
+        def query(self, *a):
+            return FakeQuery()
+
+        def commit(self):
+            pass
+
+        def close(self):
+            pass
+
+    return srv, mcp_oauth.DbTokenStorage("srv-1", session_factory=lambda: FakeSession())
+
+
+def test_load_falls_back_to_empty_dict_for_non_dict_json():
+    # A corrupted/migrated oauth_tokens column holding a JSON array, not an
+    # object, must not crash _load()'s callers with AttributeError.
+    _srv, storage = _fake_storage('["stale", "data"]')
+    assert storage._load() == {}
+
+
+def test_get_tokens_returns_none_for_non_dict_oauth_tokens():
+    _srv, storage = _fake_storage("42")
+
+    async def go():
+        return await storage.get_tokens()
+
+    assert asyncio.run(go()) is None
+
+
+def test_update_recovers_from_non_dict_oauth_tokens():
+    # _update() must not raise TypeError trying to item-assign into a list.
+    srv, storage = _fake_storage('["stale", "data"]')
+    storage._update("tokens", {"access_token": "new"})
+    assert json.loads(srv.oauth_tokens) == {"tokens": {"access_token": "new"}}
diff --git a/tests/test_memory_cli_add_nondict.py b/tests/test_memory_cli_add_nondict.py
new file mode 100644
index 0000000000..87ffd53d9b
--- /dev/null
+++ b/tests/test_memory_cli_add_nondict.py
@@ -0,0 +1,46 @@
+"""cmd_add (scripts/odysseus-memory) must tolerate a non-dict row in the
+existing store. Every other command funnels load_all() through
+`_memory_entries()` (which drops non-dicts), but cmd_add iterated the raw
+list in its dedup check: `any(e.get("id") == ... for e in all_entries)`
+crashed with AttributeError on a corrupt/hand-edited memory.json row that
+is not a dict. The isinstance check short-circuits before `.get`.
+"""
+import importlib.machinery
+import importlib.util
+import sys
+import types
+from pathlib import Path
+from types import SimpleNamespace
+from unittest.mock import MagicMock
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+def _load_cli(monkeypatch):
+    svc = types.ModuleType("services.memory.memory")
+    svc.MemoryManager = MagicMock()
+    monkeypatch.setitem(sys.modules, "services.memory.memory", svc)
+    path = ROOT / "scripts" / "odysseus-memory"
+    loader = importlib.machinery.SourceFileLoader("odysseus_memory_cli_add", str(path))
+    spec = importlib.util.spec_from_loader(loader.name, loader)
+    module = importlib.util.module_from_spec(spec)
+    loader.exec_module(module)
+    return module
+
+
+def test_cmd_add_tolerates_non_dict_existing_row(monkeypatch):
+    cli = _load_cli(monkeypatch)
+    cli._mgr = MagicMock()
+    cli._mgr.add_entry.return_value = {"id": "m2", "text": "new"}
+    cli._mgr.load_all.return_value = [
+        {"id": "m1", "text": "existing"},
+        "corrupt-row",
+        None,
+    ]
+    emitted = []
+    monkeypatch.setattr(cli, "emit", lambda value, args: emitted.append(value))
+
+    cli.cmd_add(SimpleNamespace(text="new", category="fact", owner=None))
+
+    assert emitted == [{"id": "m2", "text": "new"}]
+    cli._mgr.save.assert_called_once()
diff --git a/tests/test_multiple_mcp_servers_timeout.py b/tests/test_multiple_mcp_servers_timeout.py
new file mode 100644
index 0000000000..4c0986d0b2
--- /dev/null
+++ b/tests/test_multiple_mcp_servers_timeout.py
@@ -0,0 +1,178 @@
+import asyncio
+import json
+import time
+from types import SimpleNamespace
+
+import pytest
+
+
+class FakeQuery:
+    def __init__(self, servers):
+        self._servers = servers
+
+    def filter(self, *_args, **_kwargs):
+        return self
+
+    def all(self):
+        return self._servers
+
+
+class FakeDB:
+    def __init__(self, servers):
+        self._servers = servers
+
+    def query(self, *_args, **_kwargs):
+        return FakeQuery(self._servers)
+
+    def close(self):
+        pass
+
+
+@pytest.mark.asyncio
+async def test_connect_all_enabled_runs_concurrently(monkeypatch):
+    from src.mcp_manager import McpManager
+
+    manager = McpManager()
+
+    servers = [
+        SimpleNamespace(
+            id=1,
+            name="server1",
+            transport="stdio",
+            command="cmd1",
+            args=json.dumps([]),
+            env=json.dumps({}),
+            url=None,
+        ),
+        SimpleNamespace(
+            id=2,
+            name="server2",
+            transport="stdio",
+            command="cmd2",
+            args=json.dumps([]),
+            env=json.dumps({}),
+            url=None,
+        ),
+        SimpleNamespace(
+            id=3,
+            name="server3",
+            transport="stdio",
+            command="cmd3",
+            args=json.dumps([]),
+            env=json.dumps({}),
+            url=None,
+        ),
+    ]
+
+    # Patch the SessionLocal used by connect_all_enabled().
+    import src.mcp_manager as mcp_manager
+
+    monkeypatch.setattr(
+        mcp_manager,
+        "SessionLocal",
+        lambda: FakeDB(servers),
+    )
+
+    async def fake_connect_with_timeout(_server):
+        await asyncio.sleep(1)
+
+    # We're testing that connect_all_enabled launches these concurrently,
+    # not the implementation of connect_server().
+    monkeypatch.setattr(
+        manager,
+        "_connect_with_timeout",
+        fake_connect_with_timeout,
+    )
+
+    start = time.perf_counter()
+
+    await manager.connect_all_enabled()
+
+    elapsed = time.perf_counter() - start
+
+    # Sequential would take ~3 seconds.
+    # Concurrent should take about 1 second.
+    assert 0.9 <= elapsed < 2.0
+
+@pytest.mark.asyncio
+async def test_connect_all_enabled_timeout_does_not_block_other_servers(monkeypatch):
+    import src.mcp_manager as mcp_manager
+    from src.mcp_manager import McpManager
+
+    manager = McpManager()
+
+    servers = [
+        SimpleNamespace(
+            id=1,
+            name="fast1",
+            transport="stdio",
+            command="cmd1",
+            args=json.dumps([]),
+            env=json.dumps({}),
+            url=None,
+        ),
+        SimpleNamespace(
+            id=2,
+            name="slow",
+            transport="stdio",
+            command="cmd2",
+            args=json.dumps([]),
+            env=json.dumps({}),
+            url=None,
+        ),
+        SimpleNamespace(
+            id=3,
+            name="fast2",
+            transport="stdio",
+            command="cmd3",
+            args=json.dumps([]),
+            env=json.dumps({}),
+            url=None,
+        ),
+    ]
+
+    monkeypatch.setattr(
+        mcp_manager,
+        "SessionLocal",
+        lambda: FakeDB(servers),
+    )
+
+    completed = []
+
+    async def fake_connect_server(server_id, **kwargs):
+        if server_id == 2:
+            # Simulate a hung connection.
+            await asyncio.sleep(30)
+        else:
+            await asyncio.sleep(0.1)
+            completed.append(server_id)
+
+    monkeypatch.setattr(
+        manager,
+        "connect_server",
+        fake_connect_server,
+    )
+
+    #
+    # Don't actually wait 20 seconds during the test.
+    # Replace asyncio.wait_for used by mcp_manager with a much shorter timeout.
+    #
+    real_wait_for = asyncio.wait_for
+
+    async def short_wait_for(awaitable, timeout):
+        return await real_wait_for(awaitable, timeout=0.2)
+
+    monkeypatch.setattr(
+        mcp_manager.asyncio,
+        "wait_for",
+        short_wait_for,
+    )
+
+    start = time.perf_counter()
+
+    await manager.connect_all_enabled()
+
+    elapsed = time.perf_counter() - start
+
+    assert set(completed) == {1, 3}
+    assert elapsed < 1
\ No newline at end of file
diff --git a/tests/test_parse_msg_content_jsonlike_string.py b/tests/test_parse_msg_content_jsonlike_string.py
index 87d44fe2b5..76a7d5ece2 100644
--- a/tests/test_parse_msg_content_jsonlike_string.py
+++ b/tests/test_parse_msg_content_jsonlike_string.py
@@ -1,13 +1,9 @@
-"""A plain text message that merely *looks* like a JSON array of objects must
-NOT be silently re-parsed into a list on reload.
-
-_parse_msg_content de-serializes multimodal (image/audio) content back into a
-list of content blocks. The old heuristic accepted ANY string that started
-with "[{" and contained the substring '"type"'. A user who pasted an API
-schema / sample such as `[{"type": "object", "name": "foo"}]` therefore had
-their text message permanently corrupted into a Python list on the next
-session hydration. The fix restricts the round-trip to lists whose elements
-are all recognized content-block types (text/image_url/audio/...).
+"""Persistence contracts for JSON-like text and multimodal chat content.
+
+Plain text that resembles a JSON content-block list must remain an exact
+string. Real provider multimodal blocks follow the durable attachment
+contract: readable text plus stable attachment metadata is persisted, while
+raw inline media bytes are omitted.
 """
 import tempfile
 import uuid
@@ -65,16 +61,48 @@ def test_jsonlike_user_string_not_corrupted(manager):
     assert reloaded.history[0].content == text
 
 
-def test_real_multimodal_content_still_round_trips(manager):
+def test_real_multimodal_content_persists_reference_without_base64(manager):
     sid = "sess-" + uuid.uuid4().hex[:8]
     _make_session(sid)
+    attachment_id = "a" * 32 + ".png"
     multimodal = [
         {"type": "text", "text": "what is this?"},
         {"type": "image_url", "image_url": {"url": "data:image/png;base64,AAAA"}},
     ]
-    msgs = [ChatMessage(role="user", content=multimodal)]
+    metadata = {
+        "attachments": [
+            {
+                "id": attachment_id,
+                "name": "diagram.png",
+                "mime": "image/png",
+                "size": 4,
+                "checksum_sha256": "sha256-digest",
+            }
+        ]
+    }
+    msgs = [ChatMessage(role="user", content=multimodal, metadata=metadata)]
     assert manager.replace_messages(sid, msgs) is True
 
+    expected = (
+        "what is this?\n"
+        "[1 inline media payload omitted]\n"
+        f"[Attachment: diagram.png | id={attachment_id} | mime=image/png | "
+        "size=4 bytes | sha256=sha256-digest]"
+    )
+
+    db = _TS()
+    try:
+        stored = db.query(cdb.ChatMessage).filter_by(session_id=sid).one()
+        assert stored.content == expected
+        assert "what is this?" in stored.content
+        assert attachment_id in stored.content
+        assert "data:image/png;base64,AAAA" not in stored.content
+        assert "base64" not in stored.content
+        assert "AAAA" not in stored.content
+    finally:
+        db.close()
+
     manager.sessions.clear()
     reloaded = manager.get_session(sid)
-    assert reloaded.history[0].content == multimodal
+    assert reloaded.history[0].content == expected
+    assert reloaded.history[0].metadata["attachments"][0]["id"] == attachment_id
diff --git a/tests/test_replace_messages_multimodal.py b/tests/test_replace_messages_multimodal.py
index ec89515776..19a668fa78 100644
--- a/tests/test_replace_messages_multimodal.py
+++ b/tests/test_replace_messages_multimodal.py
@@ -1,14 +1,9 @@
-"""replace_messages must JSON-serialize multimodal (list) content.
-
-A chat with an image/audio attachment carries list content. When such a
-chat is compacted, the manual-compaction path calls replace_messages with
-the retained messages. replace_messages wrote message.content straight into
-the Text column, so SQLAlchemy bound the list\'s single-quoted repr. On
-reload _parse_msg_content only de-serializes a string that contains the
-double-quoted "type", so the repr failed the check and the message came
-back as a corrupted string blob - the attachment was destroyed. The
-sibling _persist_message json.dumps-es list content; replace_messages did
-not.
+"""replace_messages must persist readable, path-free multimodal history.
+
+Live model input may contain provider-specific media blocks and inline data
+URLs. Compaction uses replace_messages for the retained transcript, which must
+store readable text plus stable structured attachment references without
+copying raw base64 payloads into ChatMessage.content.
 """
 import uuid
 
@@ -27,6 +22,7 @@ def manager(monkeypatch):
     monkeypatch.setattr(sm, "SessionLocal", _TS)
     mgr = sm.SessionManager.__new__(sm.SessionManager)
     mgr.sessions = {}
+    mgr.upload_handler = None
     return mgr
 
 
@@ -41,33 +37,71 @@ def _make_session(sid, owner="alice"):
         db.close()
 
 
-def test_multimodal_content_round_trips_through_replace_messages(manager):
+def test_multimodal_content_persists_text_and_attachment_ref_without_payload(manager):
     sid = "sess-" + uuid.uuid4().hex[:8]
     _make_session(sid)
 
+    upload_id = "a" * 32 + ".png"
     multimodal = [
         {"type": "text", "text": "what is this?"},
         {"type": "image_url", "image_url": {"url": "data:image/png;base64,AAAA"}},
     ]
-    msgs = [ChatMessage(role="user", content=multimodal)]
+    msgs = [ChatMessage(
+        role="user",
+        content=multimodal,
+        metadata={
+            "attachments": [{
+                "id": upload_id,
+                "name": "diagram.png",
+                "mime": "image/png",
+                "size": 4,
+                "checksum_sha256": "sha256-digest",
+            }]
+        },
+    )]
     assert manager.replace_messages(sid, msgs) is True
 
+    expected = (
+        "what is this?\n"
+        "[1 inline media payload omitted]\n"
+        f"[Attachment: diagram.png | id={upload_id} | mime=image/png | "
+        "size=4 bytes | sha256=sha256-digest]"
+    )
+
+    db = _TS()
+    try:
+        stored = db.query(cdb.ChatMessage).filter_by(session_id=sid).one()
+        assert stored.content == expected
+        assert "data:image/png;base64,AAAA" not in stored.content
+        assert "base64" not in stored.content
+        assert "AAAA" not in stored.content
+    finally:
+        db.close()
+
     # Drop the in-memory cache so the next read hydrates from the DB.
     manager.sessions.clear()
     reloaded = manager.get_session(sid)
     assert len(reloaded.history) == 1
-    # Content must come back as the original list, not a repr string blob.
-    assert reloaded.history[0].content == multimodal
+    persisted = reloaded.history[0].content
+    assert isinstance(persisted, str)
+    assert persisted == expected
+    assert reloaded.history[0].metadata["attachments"][0]["id"] == upload_id
+    assert (
+        reloaded.history[0].metadata["attachments"][0]["checksum_sha256"]
+        == "sha256-digest"
+    )
 
 
-def test_plain_string_content_still_round_trips(manager):
+def test_jsonlike_plain_string_content_still_round_trips(manager):
     sid = "sess-" + uuid.uuid4().hex[:8]
     _make_session(sid)
-    msgs = [ChatMessage(role="user", content="just text")]
+    text = '[{"type": "object", "name": "foo"}]'
+    msgs = [ChatMessage(role="user", content=text)]
     assert manager.replace_messages(sid, msgs) is True
     manager.sessions.clear()
     reloaded = manager.get_session(sid)
-    assert reloaded.history[0].content == "just text"
+    assert isinstance(reloaded.history[0].content, str)
+    assert reloaded.history[0].content == text
 
 
 def test_replace_messages_keeps_history_alias_for_context_messages(manager):
diff --git a/tests/test_replace_messages_upload_reservations.py b/tests/test_replace_messages_upload_reservations.py
new file mode 100644
index 0000000000..37a86d16e0
--- /dev/null
+++ b/tests/test_replace_messages_upload_reservations.py
@@ -0,0 +1,259 @@
+"""Upload lifecycle guarantees for compaction's replace_messages path."""
+
+import concurrent.futures
+import json
+import os
+import threading
+import uuid
+
+import pytest
+from sqlalchemy import event
+
+import core.database as cdb
+import core.session_manager as session_manager_module
+from core.models import ChatMessage
+from src.upload_handler import UploadHandler
+from tests.helpers.sqlite_db import make_temp_sqlite
+
+
+OLD_TIMESTAMP = "2000-01-01T00:00:00"
+
+
+@pytest.fixture
+def manager_db(monkeypatch):
+    SessionLocal, engine, tmpfile = make_temp_sqlite(cdb.Base.metadata)
+    monkeypatch.setattr(session_manager_module, "SessionLocal", SessionLocal)
+    manager = session_manager_module.SessionManager.__new__(
+        session_manager_module.SessionManager
+    )
+    manager.sessions = {}
+    manager.upload_handler = None
+    try:
+        yield manager, SessionLocal, engine
+    finally:
+        engine.dispose()
+        tmpfile.close()
+        try:
+            os.unlink(tmpfile.name)
+        except OSError:
+            pass
+
+
+def _seed_session(SessionLocal, *, owner="alice", content="existing durable history"):
+    session_id = "replace-" + uuid.uuid4().hex
+    db = SessionLocal()
+    try:
+        db.add(cdb.Session(
+            id=session_id,
+            owner=owner,
+            name="Compaction reservation regression",
+            model="test-model",
+            endpoint_url="http://localhost:11434",
+            archived=False,
+            message_count=1,
+        ))
+        db.add(cdb.ChatMessage(
+            id="message-" + uuid.uuid4().hex,
+            session_id=session_id,
+            role="user",
+            content=content,
+            meta_data=json.dumps({"source": "before-replacement"}),
+        ))
+        db.commit()
+    finally:
+        db.close()
+    return session_id
+
+
+def _attachment_message(upload_id, text):
+    return ChatMessage(
+        role="user",
+        content=text,
+        metadata={
+            "attachments": [{
+                "id": upload_id,
+                "name": f"{text}.txt",
+                "mime": "text/plain",
+                "size": len(text),
+            }]
+        },
+    )
+
+
+def _durable_messages(SessionLocal, session_id):
+    db = SessionLocal()
+    try:
+        return [
+            (message.role, message.content, message.meta_data)
+            for message in db.query(cdb.ChatMessage)
+            .filter(cdb.ChatMessage.session_id == session_id)
+            .order_by(cdb.ChatMessage.timestamp, cdb.ChatMessage.id)
+            .all()
+        ]
+    finally:
+        db.close()
+
+
+def test_replace_messages_reserves_every_incoming_attachment_before_delete(
+    manager_db,
+    monkeypatch,
+):
+    manager, SessionLocal, engine = manager_db
+    session_id = _seed_session(SessionLocal)
+    manager.upload_handler = object()
+    incoming = [
+        _attachment_message("1" * 32 + ".txt", "first"),
+        _attachment_message("2" * 32 + ".txt", "second"),
+    ]
+    message_mutations = []
+    reservation_calls = []
+
+    def record_sql(_conn, _cursor, statement, _parameters, _context, _executemany):
+        normalized = statement.lstrip().upper()
+        if normalized.startswith(("DELETE FROM CHAT_MESSAGES", "INSERT INTO CHAT_MESSAGES")):
+            message_mutations.append(normalized.split(maxsplit=1)[0])
+
+    def reserve(handler, owner, content, metadata):
+        assert message_mutations == []
+        reservation_calls.append((handler, owner, content, metadata))
+        return None
+
+    event.listen(engine, "before_cursor_execute", record_sql)
+    monkeypatch.setattr(
+        session_manager_module,
+        "reserve_message_upload_references",
+        reserve,
+    )
+    try:
+        assert manager.replace_messages(session_id, incoming) is True
+    finally:
+        event.remove(engine, "before_cursor_execute", record_sql)
+
+    assert [call[2] for call in reservation_calls] == ["first", "second"]
+    assert all(call[0] is manager.upload_handler for call in reservation_calls)
+    assert all(call[1] == "alice" for call in reservation_calls)
+    assert message_mutations == ["DELETE", "INSERT"]
+
+
+def test_replace_messages_reservation_failure_leaves_durable_history_unchanged(
+    manager_db,
+    monkeypatch,
+):
+    manager, SessionLocal, engine = manager_db
+    session_id = _seed_session(SessionLocal)
+    before = _durable_messages(SessionLocal, session_id)
+    manager.upload_handler = object()
+    missing_upload_id = "4" * 32 + ".txt"
+    incoming = [
+        _attachment_message("3" * 32 + ".txt", "available"),
+        _attachment_message(missing_upload_id, "missing"),
+    ]
+    calls = []
+    message_mutations = []
+
+    def record_sql(_conn, _cursor, statement, _parameters, _context, _executemany):
+        normalized = statement.lstrip().upper()
+        if normalized.startswith(("DELETE FROM CHAT_MESSAGES", "INSERT INTO CHAT_MESSAGES")):
+            message_mutations.append(normalized.split(maxsplit=1)[0])
+
+    def reserve(_handler, _owner, content, _metadata):
+        calls.append(content)
+        return missing_upload_id if content == "missing" else None
+
+    event.listen(engine, "before_cursor_execute", record_sql)
+    monkeypatch.setattr(
+        session_manager_module,
+        "reserve_message_upload_references",
+        reserve,
+    )
+    try:
+        assert manager.replace_messages(session_id, incoming) is False
+    finally:
+        event.remove(engine, "before_cursor_execute", record_sql)
+
+    assert calls == ["available", "missing"]
+    assert message_mutations == []
+    assert _durable_messages(SessionLocal, session_id) == before
+    assert [message.content for message in manager.sessions[session_id].history] == [
+        "existing durable history"
+    ]
+    assert all("_db_id" not in (message.metadata or {}) for message in incoming)
+
+
+def test_cleanup_cannot_delete_attachment_during_concurrent_compaction_replacement(
+    manager_db,
+    monkeypatch,
+    tmp_path,
+):
+    manager, SessionLocal, _engine = manager_db
+    session_id = _seed_session(SessionLocal)
+    base_dir = tmp_path / "base"
+    upload_dir = tmp_path / "uploads"
+    base_dir.mkdir()
+    upload_dir.mkdir()
+    handler = UploadHandler(str(base_dir), str(upload_dir))
+    manager.upload_handler = handler
+
+    upload_id = "5" * 32 + ".txt"
+    upload_hash = "6" * 64
+    dated_dir = upload_dir / "2000" / "01" / "01"
+    dated_dir.mkdir(parents=True)
+    upload_path = dated_dir / upload_id
+    upload_path.write_text("attachment retained by compaction", encoding="utf-8")
+    upload_row = {
+        "id": upload_id,
+        "path": str(upload_path),
+        "mime": "text/plain",
+        "size": upload_path.stat().st_size,
+        "name": "compaction.txt",
+        "original_name": "compaction.txt",
+        "hash": upload_hash,
+        "checksum_sha256": upload_hash,
+        "uploaded_at": OLD_TIMESTAMP,
+        "created_at": OLD_TIMESTAMP,
+        "last_accessed": OLD_TIMESTAMP,
+        "owner": "alice",
+    }
+    (upload_dir / "uploads.json").write_text(
+        json.dumps({f"alice:{upload_hash}": upload_row}),
+        encoding="utf-8",
+    )
+    handler._index_cache = None
+
+    reservation_write_entered = threading.Event()
+    release_reservation_write = threading.Event()
+    real_atomic_write = handler._atomic_write_json
+
+    def block_reservation_write(path, data, *, sync_backup=False):
+        refreshed = any(
+            isinstance(row, dict)
+            and row.get("id") == upload_id
+            and row.get("last_accessed") != OLD_TIMESTAMP
+            for row in data.values()
+        )
+        if sync_backup and refreshed and not reservation_write_entered.is_set():
+            reservation_write_entered.set()
+            assert release_reservation_write.wait(5)
+        return real_atomic_write(path, data, sync_backup=sync_backup)
+
+    monkeypatch.setattr(handler, "_atomic_write_json", block_reservation_write)
+    incoming = [_attachment_message(upload_id, "retained after compaction")]
+
+    with concurrent.futures.ThreadPoolExecutor(max_workers=2) as pool:
+        replace_future = pool.submit(manager.replace_messages, session_id, incoming)
+        assert reservation_write_entered.wait(5)
+        cleanup_future = pool.submit(handler.cleanup_old_uploads, set(), set())
+        try:
+            with pytest.raises(concurrent.futures.TimeoutError):
+                cleanup_future.result(timeout=0.1)
+        finally:
+            release_reservation_write.set()
+
+        assert replace_future.result(timeout=5) is True
+        assert cleanup_future.result(timeout=5) == 0
+
+    assert upload_path.is_file()
+    assert handler.resolve_upload(upload_id, owner="alice") is not None
+    durable = _durable_messages(SessionLocal, session_id)
+    assert len(durable) == 1
+    assert json.loads(durable[0][2])["attachments"][0]["id"] == upload_id
diff --git a/tests/test_scheduled_poll_race.py b/tests/test_scheduled_poll_race.py
new file mode 100644
index 0000000000..92575526ec
--- /dev/null
+++ b/tests/test_scheduled_poll_race.py
@@ -0,0 +1,116 @@
+"""Regression: two concurrent callers of `_scheduled_poll_once` (the
+in-process 30s poller and the `odysseus-mail poll-scheduled` CLI, which the
+project's own docstrings warn can race on the same SQLite when
+ODYSSEUS_INPROCESS_POLLERS is left enabled alongside an external cron/systemd
+driver) must not both send the same scheduled email.
+
+The old code selected pending rows, then only updated their status to 'sent'
+*after* the SMTP send completed - two overlapping calls can both SELECT the
+same 'pending' row before either UPDATEs it, so both send it. The fix adds
+an atomic claim step (`UPDATE ... SET status='sending' WHERE status='pending'`)
+before any work happens; only the caller whose UPDATE actually changes a row
+proceeds, the other sees rowcount == 0 and skips it.
+
+This test drives two real threads through the real `_scheduled_poll_once`
+against a shared SQLite file, synchronized with a barrier so both reach the
+SELECT at (as close to) the same moment as possible, and asserts the send
+callback fired exactly once.
+"""
+import sqlite3
+import threading
+import time
+
+
+def test_concurrent_pollers_do_not_double_send(tmp_path, monkeypatch):
+    import routes.email_helpers as email_helpers
+    import routes.email_pollers as email_pollers
+
+    db_path = tmp_path / "scheduled_emails.db"
+    monkeypatch.setattr(email_helpers, "SCHEDULED_DB", db_path)
+    monkeypatch.setattr(email_pollers, "SCHEDULED_DB", db_path)
+    email_helpers._init_scheduled_db()
+
+    conn = sqlite3.connect(db_path)
+    conn.execute(
+        """
+        INSERT INTO scheduled_emails
+        (id, to_addr, subject, body, attachments, send_at, created_at, status, account_id, owner)
+        VALUES (?, ?, ?, ?, ?, ?, ?, 'pending', ?, ?)
+        """,
+        (
+            "sched-race-1",
+            "recipient@example.com",
+            "Subject",
+            "Body",
+            "[]",
+            "2000-01-01T00:00:00",
+            "1999-12-31T00:00:00",
+            "acct-alice",
+            "alice",
+        ),
+    )
+    conn.commit()
+    conn.close()
+
+    send_calls = []
+    send_lock = threading.Lock()
+    barrier = threading.Barrier(2)
+
+    def fake_get_email_config(account_id=None, owner=""):
+        return {
+            "from_address": "alice@example.com",
+            "smtp_host": "smtp.example.com",
+            "smtp_user": "alice@example.com",
+            "smtp_password": "secret",
+        }
+
+    def fake_send_smtp_message(*args, **kwargs):
+        # Widen the window between the claim and the actual send so a
+        # buggy (unclaimed) second poller has every opportunity to also
+        # get past its SELECT and attempt to send.
+        time.sleep(0.05)
+        with send_lock:
+            send_calls.append(threading.get_ident())
+
+    class FakeImap:
+        def __init__(self, account_id=None, owner=""):
+            pass
+
+        def __enter__(self):
+            return self
+
+        def __exit__(self, exc_type, exc, tb):
+            return False
+
+        def append(self, folder, flags, date_time, message):
+            pass
+
+    monkeypatch.setattr(email_pollers, "_get_email_config", fake_get_email_config)
+    monkeypatch.setattr(email_pollers, "_send_smtp_message", fake_send_smtp_message)
+    monkeypatch.setattr(email_pollers, "_imap", FakeImap)
+    monkeypatch.setattr(email_pollers, "_detect_sent_folder", lambda imap: "Sent")
+    monkeypatch.setattr(email_pollers, "_cleanup_compose_uploads", lambda attachments: None)
+
+    results = []
+
+    def _run():
+        barrier.wait()
+        results.append(email_pollers._scheduled_poll_once())
+
+    threads = [threading.Thread(target=_run) for _ in range(2)]
+    for t in threads:
+        t.start()
+    for t in threads:
+        t.join(timeout=5)
+
+    assert len(send_calls) == 1, (
+        f"expected exactly one send for the racing pollers, got {len(send_calls)}: "
+        "the second poller must lose the atomic claim and skip the row"
+    )
+
+    conn = sqlite3.connect(db_path)
+    status = conn.execute(
+        "SELECT status FROM scheduled_emails WHERE id=?", ("sched-race-1",)
+    ).fetchone()[0]
+    conn.close()
+    assert status == "sent"
diff --git a/tests/test_skill_importer.py b/tests/test_skill_importer.py
index eecca614f5..d7822711bb 100644
--- a/tests/test_skill_importer.py
+++ b/tests/test_skill_importer.py
@@ -71,7 +71,7 @@ def get(self, url, headers=None):
     monkeypatch.setattr("services.memory.skill_importer.httpx.Client", _Client)
     monkeypatch.setattr(
         "services.memory.skill_importer.check_outbound_url",
-        lambda url: (True, ""),
+        lambda url, **kwargs: (True, ""),
     )
     with pytest.raises(SkillImportError, match="redirect target"):
         _fetch_bytes("https://raw.githubusercontent.com/o/r/main/SKILL.md")
@@ -91,7 +91,7 @@ def test_list_github_dir_accepts_api_github_response(monkeypatch):
     )
     monkeypatch.setattr(
         "services.memory.skill_importer.check_outbound_url",
-        lambda url: (True, ""),
+        lambda url, **kwargs: (True, ""),
     )
 
     class _Resp:
@@ -146,7 +146,7 @@ def get(self, url, headers=None):
     monkeypatch.setattr("services.memory.skill_importer.httpx.Client", _Client)
     monkeypatch.setattr(
         "services.memory.skill_importer.check_outbound_url",
-        lambda url: (True, ""),
+        lambda url, **kwargs: (True, ""),
     )
 
 
diff --git a/tests/test_skill_importer_ssrf_redirect.py b/tests/test_skill_importer_ssrf_redirect.py
new file mode 100644
index 0000000000..800be633fa
--- /dev/null
+++ b/tests/test_skill_importer_ssrf_redirect.py
@@ -0,0 +1,123 @@
+"""Skill importer SSRF hardening: redirects must be re-validated per hop.
+
+The importer follows redirects manually (`_get_checked`) and re-runs the SSRF
+guard on every hop with ``block_private=True``, matching the hardened web-fetch
+path in ``services/search/content.py:_get_public_url``. Previously it used
+``httpx``'s ``follow_redirects=True`` with the lenient guard on the *initial*
+URL only, so a ``3xx`` to an internal/metadata address was still connected to.
+
+These tests are hermetic: every host is an IP literal, so ``check_outbound_url``
+resolves them locally (``getaddrinfo`` on a numeric address does no DNS) and no
+network access is required. The HTTP layer is faked so no real request is made.
+"""
+import pytest
+
+from services.memory import skill_importer
+from services.memory.skill_importer import (
+    SkillImportError,
+    _check_fetch_url,
+    _fetch_bytes,
+    _get_checked,
+    parse_skill_source,
+)
+
+# Clearly-public, non-reserved IP literals for the initial (allowed) hop.
+PUBLIC_A = "https://1.1.1.1/skill"
+PUBLIC_B = "https://8.8.8.8/skill"
+# Internal redirect targets that must be refused before connection.
+LOOPBACK = "http://127.0.0.1/latest"
+METADATA = "http://169.254.169.254/latest/meta-data/"
+
+
+def _install_fake_client(monkeypatch, *, redirect_from, redirect_to):
+    """Replace httpx.Client so `redirect_from` 302s to `redirect_to`, and any
+    other URL returns 200. No real socket is opened."""
+
+    class _Resp:
+        def __init__(self, url, status, location):
+            self.url = url
+            self.status_code = status
+            self.headers = {"location": location} if location else {}
+            self.content = b"ok"
+            self.text = ""
+
+        def raise_for_status(self):
+            return None
+
+        def json(self):
+            return {}
+
+    class _Client:
+        def __init__(self, *args, **kwargs):
+            # Safety invariant: the importer follows redirects by hand and
+            # re-runs the SSRF guard per hop, so it MUST disable httpx's own
+            # redirect following. Asserting ``follow_redirects is False`` here
+            # (not merely accepting the kwarg) makes any regression to
+            # ``follow_redirects=True`` fail these tests instead of passing
+            # silently — httpx being faked would otherwise hide the change.
+            assert kwargs.get("follow_redirects") is False, (
+                "skill importer must construct httpx.Client with "
+                "follow_redirects=False; got "
+                f"{kwargs.get('follow_redirects')!r}"
+            )
+
+        def __enter__(self):
+            return self
+
+        def __exit__(self, *args):
+            return False
+
+        def get(self, url, headers=None):
+            if url == redirect_from:
+                return _Resp(url, 302, redirect_to)
+            return _Resp(url, 200, None)
+
+    monkeypatch.setattr(skill_importer.httpx, "Client", _Client)
+
+
+# --- Guard unit: block_private=True refuses internal, allows public ----------
+
+@pytest.mark.parametrize("url", [LOOPBACK, METADATA, "http://10.0.0.5/", "http://[::1]/"])
+def test_check_fetch_url_blocks_internal(url):
+    with pytest.raises(SkillImportError):
+        _check_fetch_url(url)
+
+
+@pytest.mark.parametrize("url", [PUBLIC_A, PUBLIC_B])
+def test_check_fetch_url_allows_public(url):
+    # Should not raise for a public IP literal.
+    _check_fetch_url(url)
+
+
+# --- Redirect revalidation: the core regression ------------------------------
+
+@pytest.mark.parametrize("internal", [LOOPBACK, METADATA])
+def test_get_checked_blocks_redirect_to_internal(monkeypatch, internal):
+    _install_fake_client(monkeypatch, redirect_from=PUBLIC_A, redirect_to=internal)
+    with pytest.raises(SkillImportError, match="blocked"):
+        _get_checked(PUBLIC_A)
+
+
+@pytest.mark.parametrize("internal", [LOOPBACK, METADATA])
+def test_fetch_bytes_blocks_redirect_to_internal(monkeypatch, internal):
+    # Higher-level: the public fetch helpers inherit the per-hop guard.
+    _install_fake_client(monkeypatch, redirect_from=PUBLIC_A, redirect_to=internal)
+    with pytest.raises(SkillImportError, match="blocked"):
+        _fetch_bytes(PUBLIC_A)
+
+
+def test_skills_sh_entry_blocks_redirect_to_metadata(monkeypatch):
+    # The skills.sh unwrap path (user-supplied host) must also revalidate hops.
+    raw = "http://1.1.1.1/skills.sh"  # contains "skills.sh", not "github.com"
+    _install_fake_client(monkeypatch, redirect_from=raw, redirect_to=METADATA)
+    with pytest.raises(SkillImportError, match="blocked"):
+        parse_skill_source(raw)
+
+
+# --- Positive: a legitimate public->public redirect is still followed --------
+
+def test_get_checked_follows_public_redirect(monkeypatch):
+    _install_fake_client(monkeypatch, redirect_from=PUBLIC_A, redirect_to=PUBLIC_B)
+    resp = _get_checked(PUBLIC_A)
+    assert resp.status_code == 200
+    assert str(resp.url) == PUBLIC_B
diff --git a/tests/test_tool_policy.py b/tests/test_tool_policy.py
index aecbdce166..3664b06251 100644
--- a/tests/test_tool_policy.py
+++ b/tests/test_tool_policy.py
@@ -6,7 +6,12 @@
 import src.agent_loop as al
 from src.agent_tools import ToolBlock
 from src.tool_execution import execute_tool_block
-from src.tool_policy import build_effective_tool_policy, detect_guide_only_turn
+from src.tool_policy import (
+    WEB_TOOL_NAMES,
+    build_effective_tool_policy,
+    detect_guide_only_turn,
+    web_search_enabled_for_turn,
+)
 
 
 def _collect(gen):
@@ -76,6 +81,116 @@ def test_normal_policy_preserves_existing_disabled_tools():
     assert not policy.blocks("bash")
 
 
+def test_web_search_enabled_for_turn_requires_explicit_enable():
+    assert web_search_enabled_for_turn(None, None) is False
+    assert web_search_enabled_for_turn("true", None) is True
+    assert web_search_enabled_for_turn(None, "true") is True
+    assert web_search_enabled_for_turn(True, None) is True
+    assert web_search_enabled_for_turn("false", "true") is False
+    assert web_search_enabled_for_turn(False, "true") is False
+
+
+def _schema_names(tools):
+    return {
+        tool.get("function", {}).get("name") or tool.get("name")
+        for tool in (tools or [])
+    }
+
+
+def test_agent_loop_web_intent_preserves_disabled_web_tools(monkeypatch):
+    _patch_loop_basics(monkeypatch)
+    sent_tools = []
+
+    async def _fake_stream(_candidates, messages, **kwargs):
+        sent_tools.append(kwargs.get("tools"))
+        yield _delta_chunk("ok")
+        yield "data: [DONE]\n\n"
+
+    monkeypatch.setattr(al, "stream_llm_with_fallback", _fake_stream, raising=False)
+
+    _collect(
+        al.stream_agent_loop(
+            "https://api.openai.com/v1",
+            "gpt-test",
+            [{"role": "user", "content": "please look up the latest CVEs"}],
+            max_rounds=1,
+            relevant_tools=set(),
+            disabled_tools=set(WEB_TOOL_NAMES),
+        )
+    )
+
+    assert sent_tools
+    assert WEB_TOOL_NAMES.isdisjoint(_schema_names(sent_tools[0]))
+
+
+def test_agent_loop_forced_web_tools_filtered_by_disabled_tools(monkeypatch):
+    _patch_loop_basics(monkeypatch)
+    sent_tools = []
+
+    async def _fake_stream(_candidates, messages, **kwargs):
+        sent_tools.append(kwargs.get("tools"))
+        yield _delta_chunk("ok")
+        yield "data: [DONE]\n\n"
+
+    monkeypatch.setattr(al, "stream_llm_with_fallback", _fake_stream, raising=False)
+
+    _collect(
+        al.stream_agent_loop(
+            "https://api.openai.com/v1",
+            "gpt-test",
+            [{"role": "user", "content": "latest Kubernetes release"}],
+            max_rounds=1,
+            relevant_tools=set(),
+            forced_tools=set(WEB_TOOL_NAMES),
+            disabled_tools=set(WEB_TOOL_NAMES),
+        )
+    )
+
+    assert sent_tools
+    assert WEB_TOOL_NAMES.isdisjoint(_schema_names(sent_tools[0]))
+
+
+def test_agent_loop_policy_blocks_disabled_web_tool_call_before_execution(monkeypatch):
+    _patch_loop_basics(monkeypatch)
+    called = False
+
+    async def _fake_exec(*args, **kwargs):
+        nonlocal called
+        called = True
+        return ("web_search", {"output": "ran", "exit_code": 0})
+
+    async def _fake_stream(_candidates, messages, **kwargs):
+        yield _delta_chunk('```web_search\n{"query":"current CVEs"}\n```')
+        yield "data: [DONE]\n\n"
+
+    monkeypatch.setattr(al, "execute_tool_block", _fake_exec, raising=False)
+    monkeypatch.setattr(al, "stream_llm_with_fallback", _fake_stream, raising=False)
+
+    policy = build_effective_tool_policy(
+        disabled_tools=WEB_TOOL_NAMES,
+        last_user_message="please look up the latest CVEs",
+    )
+    chunks = _collect(
+        al.stream_agent_loop(
+            "http://local.test/v1",
+            "local-model",
+            [{"role": "user", "content": "please look up the latest CVEs"}],
+            max_rounds=1,
+            relevant_tools={"web_search"},
+            disabled_tools=set(policy.all_disabled_names()),
+            tool_policy=policy,
+        )
+    )
+    events = _events(chunks)
+    blocked = [event for event in events if event.get("type") == "tool_output"]
+
+    assert called is False
+    assert not any(event.get("type") == "tool_start" for event in events)
+    assert blocked
+    assert blocked[0]["tool"] == "web_search"
+    assert blocked[0]["exit_code"] == 1
+
+
 def test_executor_policy_backstop_blocks_tools():
     policy = build_effective_tool_policy(last_user_message="Do not use tools.")
     desc, result = asyncio.run(
diff --git a/tests/test_tool_task_cancelled_on_disconnect.py b/tests/test_tool_task_cancelled_on_disconnect.py
new file mode 100644
index 0000000000..cb086dd201
--- /dev/null
+++ b/tests/test_tool_task_cancelled_on_disconnect.py
@@ -0,0 +1,92 @@
+"""Regression: the tool-execution task inside stream_agent_loop must be
+cancelled (not orphaned) when the SSE consumer stops draining the generator
+early — e.g. a client disconnect mid tool-call.
+
+The drain loop in stream_agent_loop:
+
+    _tool_task = asyncio.create_task(_run_tool())
+    while True:
+        evt = await _progress_q.get()
+        if evt is None:
+            break
+        yield ...
+    desc, result = await _tool_task
+
+used to have no try/finally around it. If the generator is closed while
+suspended on `await _progress_q.get()` (which is exactly what Starlette does
+via `aclose()` when an SSE client disconnects), GeneratorExit is thrown at
+that point and `_tool_task` is abandoned mid-flight — never awaited, never
+cancelled. For a long-running `bash`/`python` tool this orphans the
+subprocess server-side with nothing left to reap it.
+
+The fix wraps the drain loop in try/finally and cancels+awaits `_tool_task`
+on early exit. This test drives the real stream_agent_loop with a fake tool
+handler that sleeps until cancelled, closes the generator mid-tool-call (the
+same way a dropped SSE connection would), and asserts the fake handler
+actually observed cancellation.
+"""
+import asyncio
+import json
+
+import src.agent_loop as al
+
+
+def test_tool_task_cancelled_on_generator_close(monkeypatch):
+    cancelled = {"v": False}
+
+    async def _slow_exec(block, *a, progress_cb=None, **k):
+        if progress_cb:
+            await progress_cb({"elapsed_s": 1, "tail": "running"})
+        try:
+            await asyncio.sleep(60)
+        except asyncio.CancelledError:
+            cancelled["v"] = True
+            raise
+        return ("bash", {"output": "ok", "exit_code": 0})
+
+    monkeypatch.setattr(al, "get_setting", lambda key, default=None: default, raising=False)
+    monkeypatch.setattr(al, "get_mcp_manager", lambda: None, raising=False)
+    monkeypatch.setattr(al, "estimate_tokens", lambda *a, **k: 10, raising=False)
+    monkeypatch.setattr(al, "execute_tool_block", _slow_exec, raising=False)
+
+    native_calls = [{"name": "bash", "arguments": json.dumps({"command": "sleep 60"})}]
+
+    async def _fake_stream(_candidates, messages, **kwargs):
+        yield f'data: {json.dumps({"delta": "Running it now."})}\n\n'
+        yield f'data: {json.dumps({"type": "tool_calls", "calls": native_calls})}\n\n'
+        yield "data: [DONE]\n\n"
+
+    monkeypatch.setattr(al, "stream_llm_with_fallback", _fake_stream, raising=False)
+
+    async def _run():
+        gen = al.stream_agent_loop(
+            "https://api.openai.com/v1", "gpt-4o",
+            [{"role": "user", "content": "run sleep 60"}],
+            max_rounds=2,
+            relevant_tools={"bash"},
+        )
+        saw_tool_start = False
+        saw_tool_progress = False
+        async for chunk in gen:
+            if '"type": "tool_start"' in chunk:
+                saw_tool_start = True
+            elif '"type": "tool_progress" ' in chunk or '"type": "tool_progress"' in chunk:
+                saw_tool_progress = True
+                break
+        assert saw_tool_start, "expected a tool_start event before the tool ran"
+        assert saw_tool_progress, "expected a tool_progress event once the fake tool started (task must exist by now)"
+        # Simulate an SSE client disconnecting mid tool-call: close the
+        # generator while it is suspended awaiting the next progress event.
+        await gen.aclose()
+        # Assert *inside* this coroutine, immediately after aclose() returns.
+        # asyncio.run()'s own shutdown sequence cancels any tasks still
+        # pending once _run() itself completes — checking after asyncio.run()
+        # returns would pass even with the bug, because that unrelated
+        # cleanup would cancel the orphaned task anyway and mask the fix.
+        assert cancelled["v"] is True, (
+            "tool task must be cancelled by stream_agent_loop's own cleanup "
+            "on generator close, not left running until asyncio.run() tears "
+            "down the loop"
+        )
+
+    asyncio.run(_run())
diff --git a/tests/test_tts_available_nonstring_provider.py b/tests/test_tts_available_nonstring_provider.py
new file mode 100644
index 0000000000..632e1cd89a
--- /dev/null
+++ b/tests/test_tts_available_nonstring_provider.py
@@ -0,0 +1,17 @@
+from services.tts.tts_service import TTSService
+
+
+def test_available_tolerates_non_string_provider(tmp_path):
+    """A hand-edited/corrupt data/settings.json can store a non-string
+    tts_provider (e.g. null or a number). available reads it and calls
+    provider.startswith("endpoint:"), which raised AttributeError on a
+    non-str. It must instead fall through and report unavailable."""
+    service = TTSService(cache_dir=str(tmp_path))
+    service._load_settings = lambda: {
+        "tts_enabled": True,
+        "tts_provider": 123,
+        "tts_model": "tts-1",
+        "tts_voice": "alloy",
+        "tts_speed": "1",
+    }
+    assert service.available is False
diff --git a/tests/test_upload_handler_cleanup.py b/tests/test_upload_handler_cleanup.py
new file mode 100644
index 0000000000..9810c2b20b
--- /dev/null
+++ b/tests/test_upload_handler_cleanup.py
@@ -0,0 +1,831 @@
+import asyncio
+import concurrent.futures
+import json
+import os
+import threading
+from datetime import datetime
+from pathlib import Path
+from types import SimpleNamespace
+
+import pytest
+from fastapi import HTTPException
+
+from core.database import (
+    Base,
+    ChatMessage as DbChatMessage,
+    CalendarCal,
+    CalendarEvent,
+    Document,
+    DocumentVersion,
+    GalleryImage,
+    Note,
+    Session as DbSession,
+)
+from src.upload_handler import (
+    UploadCleanupSafetyError,
+    UploadHandler,
+    extract_internal_upload_ids,
+    reserve_message_upload_references,
+    reserve_upload_references,
+)
+from tests.helpers.sqlite_db import make_temp_sqlite
+
+
+OLD_TIMESTAMP = "2000-01-01T00:00:00"
+
+
+class _AdminAuth:
+    is_configured = True
+
+    @staticmethod
+    def is_admin(user):
+        return user == "admin"
+
+
+class _AdminRequest:
+    headers = {}
+    state = SimpleNamespace(current_user="admin")
+    app = SimpleNamespace(state=SimpleNamespace(auth_manager=_AdminAuth()))
+
+
+def _make_handler(tmp_path: Path) -> UploadHandler:
+    base_dir = tmp_path / "base"
+    upload_dir = tmp_path / "uploads"
+    base_dir.mkdir()
+    upload_dir.mkdir()
+    return UploadHandler(str(base_dir), str(upload_dir))
+
+
+def _seed_old_uploads(handler: UploadHandler, rows: list[dict]) -> dict[str, Path]:
+    dated_dir = Path(handler.upload_dir) / "2000" / "01" / "01"
+    dated_dir.mkdir(parents=True)
+    index = {}
+    paths = {}
+    for row in rows:
+        upload_id = row["id"]
+        path = dated_dir / upload_id
+        path.write_bytes(row.get("bytes", upload_id.encode("ascii")))
+        info = {
+            "id": upload_id,
+            "path": str(path),
+            "mime": row.get("mime", "application/octet-stream"),
+            "size": path.stat().st_size,
+            "name": row.get("name", upload_id),
+            "original_name": row.get("name", upload_id),
+            "hash": row["hash"],
+            "checksum_sha256": row["hash"],
+            "uploaded_at": row.get("uploaded_at", OLD_TIMESTAMP),
+            "created_at": row.get("created_at", OLD_TIMESTAMP),
+            "last_accessed": row.get("last_accessed", OLD_TIMESTAMP),
+            "owner": row.get("owner", "alice"),
+        }
+        index[f"{info['owner']}:{info['hash']}"] = info
+        paths[upload_id] = path
+
+    Path(handler.upload_dir, "uploads.json").write_text(
+        json.dumps(index),
+        encoding="utf-8",
+    )
+    handler._index_cache = None
+    return paths
+
+
+def _manual_cleanup_endpoint(handler: UploadHandler, monkeypatch):
+    import fastapi.dependencies.utils as dependency_utils
+    from routes.upload_routes import router, setup_upload_routes
+
+    monkeypatch.setattr(dependency_utils, "ensure_multipart_is_installed", lambda: None)
+    before = len(router.routes)
+    setup_upload_routes(handler)
+    return {
+        route.endpoint.__name__: route.endpoint
+        for route in router.routes[before:]
+    }["manual_cleanup"]
+
+
+def _reference_database(monkeypatch, *, upload_id: str, gallery_hash: str = None):
+    from routes import upload_routes
+
+    SessionLocal, engine, tmpfile = make_temp_sqlite(Base.metadata)
+    db = SessionLocal()
+    try:
+        db.add(DbSession(
+            id="session-1",
+            name="Cleanup regression",
+            endpoint_url="http://localhost",
+            model="test-model",
+            owner="alice",
+        ))
+        db.add(DbChatMessage(
+            id="message-1",
+            session_id="session-1",
+            role="user",
+            content=f"[Attachment: retained.png | id={upload_id} | mime=image/png]",
+            meta_data=json.dumps({
+                "attachments": [{
+                    "id": upload_id,
+                    "name": "retained.png",
+                    "mime": "image/png",
+                    "size": 8,
+                }]
+            }),
+        ))
+        if gallery_hash:
+            db.add(GalleryImage(
+                id="gallery-cleanup-reference",
+                filename="abcdef123456.png",
+                prompt="Chat upload",
+                owner="alice",
+                file_hash=gallery_hash,
+            ))
+        db.commit()
+    finally:
+        db.close()
+
+    monkeypatch.setattr(upload_routes, "SessionLocal", SessionLocal)
+    return engine, tmpfile
+
+
+def test_admin_cleanup_preserves_referenced_upload_and_reconciles_deleted_row(
+    tmp_path,
+    monkeypatch,
+):
+    handler = _make_handler(tmp_path)
+    referenced_id = "a" * 32 + ".png"
+    unreferenced_id = "b" * 32 + ".txt"
+    gallery_id = "7" * 32 + ".png"
+    gallery_hash = "7" * 64
+    paths = _seed_old_uploads(handler, [
+        {
+            "id": referenced_id,
+            "hash": "1" * 64,
+            "mime": "image/png",
+        },
+        {
+            "id": unreferenced_id,
+            "hash": "2" * 64,
+            "mime": "text/plain",
+        },
+        {
+            "id": gallery_id,
+            "hash": gallery_hash,
+            "mime": "image/png",
+        },
+    ])
+    engine, tmpfile = _reference_database(
+        monkeypatch,
+        upload_id=referenced_id,
+        gallery_hash=gallery_hash,
+    )
+
+    try:
+        response = asyncio.run(
+            _manual_cleanup_endpoint(handler, monkeypatch)(_AdminRequest())
+        )
+    finally:
+        engine.dispose()
+        tmpfile.close()
+        try:
+            os.unlink(tmpfile.name)
+        except OSError:
+            pass
+
+    assert response == {"status": "success", "files_cleaned": 1}
+    assert paths[referenced_id].is_file()
+    referenced_info = handler.get_upload_info(referenced_id)
+    assert referenced_info is not None
+    assert handler.resolve_upload(referenced_id, owner="alice") is not None
+    assert paths[gallery_id].is_file()
+    assert handler.get_upload_info(gallery_id) is not None
+
+    assert not paths[unreferenced_id].exists()
+    assert handler.get_upload_info(unreferenced_id) is None
+    assert handler.resolve_upload(unreferenced_id, owner="alice") is None
+
+    live_index = json.loads(
+        Path(handler.upload_dir, "uploads.json").read_text(encoding="utf-8")
+    )
+    assert {info["id"] for info in live_index.values()} == {
+        referenced_id,
+        gallery_id,
+    }
+    backup_index = json.loads(
+        Path(handler.upload_dir, "uploads.json.bak").read_text(encoding="utf-8")
+    )
+    assert {info["id"] for info in backup_index.values()} == {
+        referenced_id,
+        gallery_id,
+    }
+
+    # Recovery must not resurrect the deliberately deleted row.
+    Path(handler.upload_dir, "uploads.json").write_text("{broken", encoding="utf-8")
+    handler._index_cache = None
+    assert handler.get_upload_info(unreferenced_id) is None
+    assert paths[referenced_id].parent.is_dir()
+
+
+def test_cleanup_retains_upload_and_all_rows_when_index_rows_disagree(tmp_path):
+    handler = _make_handler(tmp_path)
+    upload_id = "c" * 32 + ".txt"
+    path = _seed_old_uploads(handler, [{
+        "id": upload_id,
+        "hash": "1" * 64,
+        "mime": "text/plain",
+        "owner": "alice",
+    }])[upload_id]
+    index_path = Path(handler.upload_dir, "uploads.json")
+    index = json.loads(index_path.read_text(encoding="utf-8"))
+    alice_row = next(iter(index.values()))
+    index["bob:" + "2" * 64] = {
+        **alice_row,
+        "owner": "bob",
+        "hash": "2" * 64,
+        "checksum_sha256": "2" * 64,
+    }
+    index_path.write_text(json.dumps(index), encoding="utf-8")
+    handler._index_cache = None
+
+    assert handler.cleanup_old_uploads(set(), set()) == 0
+    assert path.is_file()
+    assert json.loads(index_path.read_text(encoding="utf-8")) == index
+
+
+def test_cleanup_retains_lone_row_without_authoritative_lifecycle_metadata(tmp_path):
+    handler = _make_handler(tmp_path)
+    upload_id = "6" * 32 + ".txt"
+    path = _seed_old_uploads(handler, [{
+        "id": upload_id,
+        "hash": "6" * 64,
+        "mime": "text/plain",
+    }])[upload_id]
+    index_path = Path(handler.upload_dir, "uploads.json")
+    index = json.loads(index_path.read_text(encoding="utf-8"))
+    row = next(iter(index.values()))
+    for field in (
+        "owner",
+        "hash",
+        "checksum_sha256",
+        "uploaded_at",
+        "created_at",
+        "last_accessed",
+    ):
+        row.pop(field)
+    index_path.write_text(json.dumps(index), encoding="utf-8")
+    handler._index_cache = None
+
+    assert handler.cleanup_old_uploads(set(), set()) == 0
+    assert path.is_file()
+    assert json.loads(index_path.read_text(encoding="utf-8")) == index
+
+
+def test_reservation_and_cleanup_are_serialized_without_dangling_references(
+    tmp_path,
+    monkeypatch,
+):
+    # Writer wins: reservation holds the shared index lock, refreshes access,
+    # then cleanup observes the refreshed row and preserves the file.
+    writer_root = tmp_path / "writer-wins"
+    writer_root.mkdir()
+    writer_handler = _make_handler(writer_root)
+    upload_id = "2" * 32 + ".txt"
+    writer_path = _seed_old_uploads(writer_handler, [{
+        "id": upload_id,
+        "hash": "2" * 64,
+        "mime": "text/plain",
+    }])[upload_id]
+    write_entered = threading.Event()
+    release_write = threading.Event()
+    real_atomic_write = writer_handler._atomic_write_json
+
+    def blocking_reservation_write(path, data, *, sync_backup=False):
+        refreshed = any(
+            isinstance(row, dict) and row.get("last_accessed") != OLD_TIMESTAMP
+            for row in data.values()
+        )
+        if sync_backup and refreshed and not write_entered.is_set():
+            write_entered.set()
+            assert release_write.wait(5)
+        return real_atomic_write(path, data, sync_backup=sync_backup)
+
+    monkeypatch.setattr(writer_handler, "_atomic_write_json", blocking_reservation_write)
+    with concurrent.futures.ThreadPoolExecutor(max_workers=2) as pool:
+        reserve_future = pool.submit(
+            writer_handler.reserve_upload,
+            upload_id,
+            owner="alice",
+        )
+        assert write_entered.wait(5)
+        cleanup_future = pool.submit(writer_handler.cleanup_old_uploads, set(), set())
+        release_write.set()
+        assert reserve_future.result(timeout=5) is not None
+        assert cleanup_future.result(timeout=5) == 0
+    assert writer_path.is_file()
+
+    # Cleanup wins: reservation cannot pass the same lock until the row and
+    # bytes are gone, then fails so a caller cannot commit a dangling reference.
+    cleanup_root = tmp_path / "cleanup-wins"
+    cleanup_root.mkdir()
+    cleanup_handler = _make_handler(cleanup_root)
+    cleanup_path = _seed_old_uploads(cleanup_handler, [{
+        "id": upload_id,
+        "hash": "3" * 64,
+        "mime": "text/plain",
+    }])[upload_id]
+    remove_entered = threading.Event()
+    release_remove = threading.Event()
+    real_remove = os.remove
+
+    def blocking_remove(candidate):
+        if os.path.realpath(candidate) == os.path.realpath(cleanup_path):
+            remove_entered.set()
+            assert release_remove.wait(5)
+        return real_remove(candidate)
+
+    monkeypatch.setattr("src.upload_handler.os.remove", blocking_remove)
+    with concurrent.futures.ThreadPoolExecutor(max_workers=2) as pool:
+        cleanup_future = pool.submit(cleanup_handler.cleanup_old_uploads, set(), set())
+        assert remove_entered.wait(5)
+        reserve_future = pool.submit(
+            cleanup_handler.reserve_upload,
+            upload_id,
+            owner="alice",
+        )
+        release_remove.set()
+        assert cleanup_future.result(timeout=5) == 1
+        assert reserve_future.result(timeout=5) is None
+    assert not cleanup_path.exists()
+
+
+def test_admin_cleanup_reference_discovery_failure_returns_503_without_deleting(
+    tmp_path,
+    monkeypatch,
+):
+    from routes import upload_routes
+
+    handler = _make_handler(tmp_path)
+    upload_id = "d" * 32 + ".png"
+    path = _seed_old_uploads(handler, [
+        {"id": upload_id, "hash": "4" * 64, "mime": "image/png"},
+    ])[upload_id]
+
+    def fail_reference_scan():
+        raise RuntimeError("database unavailable")
+
+    monkeypatch.setattr(
+        upload_routes,
+        "_collect_persisted_upload_references",
+        fail_reference_scan,
+    )
+    endpoint = _manual_cleanup_endpoint(handler, monkeypatch)
+
+    with pytest.raises(HTTPException) as exc:
+        asyncio.run(endpoint(_AdminRequest()))
+
+    assert exc.value.status_code == 503
+    assert path.is_file()
+    assert handler.get_upload_info(upload_id) is not None
+
+
+def test_cleanup_restores_index_when_file_removal_fails(tmp_path, monkeypatch):
+    handler = _make_handler(tmp_path)
+    upload_id = "e" * 32 + ".txt"
+    path = _seed_old_uploads(handler, [
+        {
+            "id": upload_id,
+            "hash": "5" * 64,
+            "mime": "text/plain",
+        },
+    ])[upload_id]
+
+    real_remove = os.remove
+
+    def fail_target_remove(candidate):
+        if os.path.realpath(candidate) == os.path.realpath(path):
+            raise PermissionError("file is in use")
+        return real_remove(candidate)
+
+    monkeypatch.setattr("src.upload_handler.os.remove", fail_target_remove)
+
+    assert handler.cleanup_old_uploads(set(), set()) == 0
+    assert path.is_file()
+    assert handler.get_upload_info(upload_id) is not None
+    assert any(
+        info["id"] == upload_id
+        for info in json.loads(
+            Path(handler.upload_dir, "uploads.json").read_text(encoding="utf-8")
+        ).values()
+    )
+    assert any(
+        info["id"] == upload_id
+        for info in json.loads(
+            Path(handler.upload_dir, "uploads.json.bak").read_text(encoding="utf-8")
+        ).values()
+    )
+
+
+def test_admin_cleanup_with_corrupt_index_returns_503_and_fails_closed(
+    tmp_path,
+    monkeypatch,
+):
+    from routes import upload_routes
+
+    handler = _make_handler(tmp_path)
+    upload_id = "9" * 32 + ".png"
+    path = _seed_old_uploads(handler, [
+        {"id": upload_id, "hash": "9" * 64, "mime": "image/png"},
+    ])[upload_id]
+    Path(handler.upload_dir, "uploads.json").write_text(
+        '{"alice:broken": {',
+        encoding="utf-8",
+    )
+    handler._index_cache = None
+
+    monkeypatch.setattr(
+        upload_routes,
+        "_collect_persisted_upload_references",
+        lambda: (set(), set()),
+    )
+    endpoint = _manual_cleanup_endpoint(handler, monkeypatch)
+
+    with pytest.raises(HTTPException) as exc:
+        asyncio.run(endpoint(_AdminRequest()))
+
+    assert exc.value.status_code == 503
+    assert path.is_file()
+
+
+def test_cleanup_with_missing_live_index_fails_closed(tmp_path):
+    handler = _make_handler(tmp_path)
+    upload_id = "8" * 32 + ".png"
+    dated_dir = Path(handler.upload_dir) / "2000" / "01" / "01"
+    dated_dir.mkdir(parents=True)
+    path = dated_dir / upload_id
+    path.write_bytes(b"unindexed bytes")
+
+    with pytest.raises(UploadCleanupSafetyError):
+        handler.cleanup_old_uploads(set(), set())
+
+    assert path.is_file()
+
+
+def test_reference_discovery_covers_all_durable_upload_stores(
+    monkeypatch,
+):
+    from routes import upload_routes
+
+    document_id = "f" * 32 + ".pdf"
+    version_id = "1" * 32 + ".pdf"
+    note_upload_id = "3" * 32 + ".png"
+    note_color_id = "2" * 32 + ".png"
+    calendar_upload_id = "4" * 32 + ".png"
+    event_upload_id = "5" * 32 + ".png"
+    event_description_id = "7" * 32 + ".txt"
+    event_location_id = "8" * 32 + ".png"
+    gallery_hash = "6" * 64
+    SessionLocal, engine, tmpfile = make_temp_sqlite(Base.metadata)
+    db = SessionLocal()
+    try:
+        db.add(DbSession(
+            id="session-2",
+            name="Reference sources",
+            endpoint_url="http://localhost",
+            model="test-model",
+            owner="alice",
+        ))
+        db.add(Document(
+            id="document-1",
+            session_id="session-2",
+            title="PDF",
+            current_content=f'<!-- pdf_source upload_id="{document_id}" -->',
+            owner="alice",
+        ))
+        db.add(DocumentVersion(
+            id="version-1",
+            document_id="document-1",
+            version_number=1,
+            content=f'<!-- pdf_form_source upload_id="{version_id}" fields="1" -->',
+        ))
+        db.add(GalleryImage(
+            id="gallery-1",
+            # Gallery filenames are normally generated 12-hex names, so this
+            # record proves retention comes from its stored content hash.
+            filename="abcdef123456.png",
+            prompt="Chat upload",
+            owner="alice",
+            file_hash=gallery_hash,
+        ))
+        db.add(Note(
+            id="note-1",
+            owner="alice",
+            title="Photo note",
+            image_url=f"/api/upload/{note_upload_id}",
+            color=f"odysseus://attachment/{note_color_id}",
+        ))
+        db.add(CalendarCal(
+            id="calendar-1",
+            owner="alice",
+            name="Personal",
+            color=f"/api/upload/{calendar_upload_id}",
+        ))
+        db.add(CalendarEvent(
+            uid="event-1",
+            calendar_id="calendar-1",
+            summary="Photo event",
+            dtstart=datetime(2026, 7, 10, 12, 0),
+            dtend=datetime(2026, 7, 10, 13, 0),
+            color=f"/api/upload/{event_upload_id}",
+            description=f"Notes: odysseus://attachment/{event_description_id}",
+            location=f"/api/upload/{event_location_id}",
+        ))
+        db.commit()
+    finally:
+        db.close()
+
+    monkeypatch.setattr(upload_routes, "SessionLocal", SessionLocal)
+    try:
+        referenced_ids, referenced_hashes = (
+            upload_routes._collect_persisted_upload_references()
+        )
+    finally:
+        engine.dispose()
+        tmpfile.close()
+        try:
+            os.unlink(tmpfile.name)
+        except OSError:
+            pass
+
+    assert {
+        document_id,
+        version_id,
+        note_upload_id,
+        note_color_id,
+        calendar_upload_id,
+        event_upload_id,
+        event_description_id,
+        event_location_id,
+    } <= referenced_ids
+    assert gallery_hash in referenced_hashes
+
+
+def test_write_reservation_extracts_only_explicit_internal_references():
+    upload_id = "a" * 32 + ".png"
+    checksum_like_text = "b" * 32
+
+    assert extract_internal_upload_ids(checksum_like_text) == set()
+    assert extract_internal_upload_ids(f"sha={checksum_like_text}") == set()
+    assert extract_internal_upload_ids({
+        "image": f"/api/upload/{upload_id}",
+        "nested": [f"odysseus://attachment/{upload_id}"],
+    }) == {upload_id}
+    assert extract_internal_upload_ids(
+        f'<!-- pdf_source upload_id="{upload_id}" -->'
+    ) == {upload_id}
+    assert extract_internal_upload_ids(
+        f"[Attachment: photo.png | id={upload_id} | mime=image/png]"
+    ) == {upload_id}
+    extensionless_id = "c" * 32
+    assert extract_internal_upload_ids(
+        f"See /api/upload/{extensionless_id}. Then continue."
+    ) == {extensionless_id}
+    assert extract_internal_upload_ids(
+        f"Attachment: odysseus://attachment/{extensionless_id}: ready"
+    ) == {extensionless_id}
+    assert extract_internal_upload_ids(f"/api/upload/{upload_id}/extra") == set()
+
+
+def test_reservation_never_uses_admin_override(tmp_path):
+    handler = _make_handler(tmp_path)
+    upload_id = "c" * 32 + ".txt"
+    _seed_old_uploads(handler, [{
+        "id": upload_id,
+        "hash": "c" * 64,
+        "mime": "text/plain",
+        "owner": "alice",
+    }])
+
+    assert reserve_upload_references(
+        handler,
+        "alice",
+        f"odysseus://attachment/{upload_id}",
+    ) is None
+    assert reserve_upload_references(
+        handler,
+        "admin",
+        f"odysseus://attachment/{upload_id}",
+    ) == upload_id
+    assert handler.reserve_upload(
+        upload_id,
+        owner="admin",
+        auth_manager=_AdminAuth(),
+        allow_admin=False,
+    ) is None
+    assert reserve_message_upload_references(
+        handler,
+        "admin",
+        "legacy attachment metadata",
+        {"attachments": [{"id": upload_id, "name": "owned.txt"}]},
+    ) == upload_id
+
+
+def test_remaining_durable_writers_reserve_before_commit(monkeypatch):
+    import core.database as database
+    import core.session_manager as session_manager_module
+    import src.database as legacy_database
+    from core.models import ChatMessage
+    from core.session_manager import SessionManager
+    from src import tool_utils
+    from src.agent_tools.document_tools import EditDocumentTool
+    from src.tools.calendar import do_manage_calendar
+    from src.tools.notes import do_manage_notes
+
+    upload_id = "6" * 32 + ".png"
+
+    class RejectingHandler:
+        def reserve_upload(self, _candidate, **_kwargs):
+            return None
+
+    handler = RejectingHandler()
+    monkeypatch.setattr(tool_utils, "_upload_handler", handler)
+
+    SessionLocal, engine, tmpfile = make_temp_sqlite(Base.metadata)
+    monkeypatch.setattr(database, "SessionLocal", SessionLocal)
+    monkeypatch.setattr(legacy_database, "SessionLocal", SessionLocal)
+    monkeypatch.setattr(legacy_database, "Document", Document, raising=False)
+    monkeypatch.setattr(
+        legacy_database,
+        "DocumentVersion",
+        DocumentVersion,
+        raising=False,
+    )
+    monkeypatch.setattr(session_manager_module, "SessionLocal", SessionLocal)
+    db = SessionLocal()
+    try:
+        db.add(DbSession(
+            id="writer-session",
+            name="Writer coverage",
+            endpoint_url="http://localhost",
+            model="test-model",
+            owner="alice",
+        ))
+        db.add(Document(
+            id="email-document",
+            session_id="writer-session",
+            title="New Email",
+            language="email",
+            current_content="To: team@example.test\nSubject: Status\n---\nOld body",
+            version_count=1,
+            owner="alice",
+        ))
+        db.commit()
+
+        manager = SessionManager()
+        manager.upload_handler = handler
+        manager._persist_message(
+            "writer-session",
+            ChatMessage(
+                "user",
+                "attachment",
+                metadata={"attachments": [{"id": upload_id}]},
+            ),
+        )
+
+        document_result = asyncio.run(EditDocumentTool().execute(
+            "<<<FIND>>>\n\n<<<REPLACE>>>\n"
+            f"See /api/upload/{upload_id}\n<<<END>>>",
+            {"doc_id": "email-document", "owner": "alice"},
+        ))
+        assert document_result["exit_code"] == 1
+        assert "no longer available" in document_result["error"]
+
+        calendar_result = asyncio.run(do_manage_calendar(
+            json.dumps({
+                "action": "create_event",
+                "summary": "Attachment review",
+                "dtstart": "2026-07-12T12:00:00",
+                "description": f"See /api/upload/{upload_id}",
+            }),
+            owner="alice",
+        ))
+        assert calendar_result["exit_code"] == 1
+        assert "no longer available" in calendar_result["error"]
+
+        note_result = asyncio.run(do_manage_notes(
+            json.dumps({
+                "action": "add",
+                "title": "Attachment note",
+                "content": f"See /api/upload/{upload_id}",
+            }),
+            owner="alice",
+        ))
+        assert note_result["exit_code"] == 1
+        assert "no longer available" in note_result["error"]
+
+        verify = SessionLocal()
+        try:
+            assert verify.query(DbChatMessage).count() == 0
+            stored_doc = verify.query(Document).filter(Document.id == "email-document").one()
+            assert stored_doc.current_content.endswith("Old body")
+            assert verify.query(CalendarEvent).count() == 0
+            assert verify.query(Note).count() == 0
+        finally:
+            verify.close()
+    finally:
+        db.close()
+        engine.dispose()
+        tmpfile.close()
+        try:
+            os.unlink(tmpfile.name)
+        except OSError:
+            pass
+
+
+def test_note_calendar_and_document_routes_reserve_before_database_writes(monkeypatch):
+    from routes.calendar_routes import EventCreate, setup_calendar_routes
+    from routes import document_routes
+    from routes.document_helpers import DocumentCreate
+    from routes.note_routes import NoteCreate, setup_note_routes
+    from src import auth_helpers
+
+    upload_id = "d" * 32 + ".png"
+
+    class RejectingHandler:
+        def __init__(self):
+            self.calls = []
+
+        def reserve_upload(self, candidate, **kwargs):
+            self.calls.append((candidate, kwargs))
+            return None
+
+    request = SimpleNamespace(
+        state=SimpleNamespace(current_user="alice", api_token=False),
+        app=SimpleNamespace(state=SimpleNamespace()),
+    )
+
+    note_handler = RejectingHandler()
+    note_router = setup_note_routes(upload_handler=note_handler)
+    create_note = next(
+        route.endpoint for route in note_router.routes
+        if route.endpoint.__name__ == "create_note"
+    )
+    with pytest.raises(HTTPException) as note_error:
+        create_note(
+            request,
+            NoteCreate(image_url=f"/api/upload/{upload_id}"),
+        )
+    assert note_error.value.status_code == 409
+    assert note_handler.calls == [
+        (upload_id, {"owner": "alice", "allow_admin": False})
+    ]
+
+    calendar_handler = RejectingHandler()
+    calendar_router = setup_calendar_routes(upload_handler=calendar_handler)
+    create_event = next(
+        route.endpoint for route in calendar_router.routes
+        if route.endpoint.__name__ == "create_event"
+    )
+    with pytest.raises(HTTPException) as calendar_error:
+        asyncio.run(create_event(
+            request,
+            EventCreate(
+                summary="Photo",
+                dtstart="2026-07-10T12:00:00",
+                color=f"odysseus://attachment/{upload_id}",
+            ),
+        ))
+    assert calendar_error.value.status_code == 409
+    assert calendar_handler.calls == [
+        (upload_id, {"owner": "alice", "allow_admin": False})
+    ]
+
+    class EmptyDb:
+        @staticmethod
+        def close():
+            return None
+
+    document_handler = RejectingHandler()
+    monkeypatch.setattr(document_routes, "SessionLocal", EmptyDb)
+    monkeypatch.setattr(
+        auth_helpers,
+        "require_privilege",
+        lambda _request, _privilege: "alice",
+    )
+    document_router = document_routes.setup_document_routes(
+        SimpleNamespace(),
+        document_handler,
+    )
+    create_document = next(
+        route.endpoint for route in document_router.routes
+        if route.endpoint.__name__ == "create_document"
+    )
+    with pytest.raises(HTTPException) as document_error:
+        asyncio.run(create_document(
+            request,
+            DocumentCreate(
+                language="markdown",
+                content=f"![image](/api/upload/{upload_id})",
+            ),
+        ))
+    assert document_error.value.status_code == 409
+    assert document_handler.calls == [
+        (upload_id, {"owner": "alice", "allow_admin": False})
+    ]