fix: harden work graph input validation

CHANGELOG.md

@@ -18,6 +18,13 @@ patch version.
 - Pinned `skills@1.5.22` distribution discovery plus a separate
   `skills@latest` forward-compatibility smoke.
 
+### Fixed
+
+- Reject non-integer manifest schema versions and blank item titles or source
+  references.
+- Fail closed when a local ticket omits its `Blocked by` declaration; tickets
+  without blockers must state `None` explicitly.
+
 ### Boundaries
 
 - The public release, anonymous-install verification, clean-home Codex and

README.md

@@ -75,7 +75,7 @@ collected only on a frozen release candidate.
 
 | Source | V0 support |
 | --- | --- |
-| `to-tickets` local one-ticket-per-file Markdown | Supported; attested to upstream `v1.2.2` |
+| `to-tickets` local one-ticket-per-file Markdown | Supported; attested to upstream `v1.2.2`; every ticket must explicitly declare `Blocked by`, using `None` when empty |
 | GitHub native sub-issues and dependencies | Supported |
 | GitHub task-list children and `## Blocked by` / `Blocked by: #N` fallback | Supported |
 | Normalized work-graph JSON | Supported |

README.zh-CN.md

@@ -1,6 +1,6 @@
 # First Tree Skills
 
-> 英文 [README.md](README.md) 是规范来源。本译文同步于 2026-08-06；若内容不一致，以英文版为准。
+> 英文 [README.md](README.md) 是规范来源。本译文同步于 2026-08-10；若内容不一致，以英文版为准。
 
 用于把结构化 agent 工作安全移入
 [First Tree](https://first-tree.ai/?utm_source=first-tree-skills&utm_medium=github&utm_campaign=readme) 的 companion skills。
@@ -56,7 +56,7 @@ Use the run-with-first-tree skill to inspect and run the tickets under
 
 ## V0 输入与边界
 
-支持：`to-tickets` v1.2.2 的一票一文件 Markdown、GitHub 原生子 issue 与依赖、正文中的 `Blocked by` fallback，以及 normalized work-graph JSON。
+支持：`to-tickets` v1.2.2 的一票一文件 Markdown（每张票必须显式声明 `Blocked by`，无依赖时写 `None`）、GitHub 原生子 issue 与依赖、正文中的 `Blocked by` fallback，以及 normalized work-graph JSON。
 
 不支持：直接消费 Wayfinder map、GitLab/custom tracker 原生 API、后台监控、自动改写源 tracker，以及把派发权限扩展到用户未授权的代码、生产或外部系统。
 

skills/run-with-first-tree/references/work-graph-contract.md

@@ -35,10 +35,12 @@ Use UTF-8 JSON:
 }
 ```
 
-The validator requires `schema_version`, `source`, and `items`. Every item
-requires every field shown above. Its `graph_digest` identifies the stable
-source, item identities, dispatchability, and blocking topology; mutable status,
-claim, and acceptance fields do not change the digest.
+The validator requires `schema_version`, `source`, and `items`.
+`schema_version` must be the JSON integer `1`; booleans and numeric strings are
+invalid. Every item requires every field shown above, and `title` and `source`
+must be non-empty strings. Its `graph_digest` identifies the stable source, item
+identities, dispatchability, and blocking topology; mutable status, claim, and
+acceptance fields do not change the digest.
 
 ## Item semantics
 
@@ -49,8 +51,9 @@ claim, and acceptance fields do not change the digest.
   or `-` so it can be reused safely in dispatch metadata.
   `AMBIGUOUS:` and `UNRESOLVED:` are reserved legacy dependency-marker
   prefixes and cannot be used as item ids.
-- `title` — human-readable ticket name.
-- `source` — absolute or project-relative path, or canonical issue URL.
+- `title` — non-empty human-readable ticket name.
+- `source` — non-empty absolute or project-relative path, or canonical issue
+  URL.
 - `status` — `open`, `completed`, or `cancelled`. A GitHub issue closed as
   `not_planned`, `duplicate`, or another non-completion reason is cancelled and
   does not release dependents.
@@ -115,6 +118,10 @@ The local builder recognizes the one-ticket-per-file shape used by
 - `**Status:** ready-for-agent` as the readiness signal; and
 - Markdown task-list items as acceptance criteria.
 
+Every local ticket must contain exactly one `Blocked by` declaration. Tickets
+without blockers must state `None` explicitly. A missing or repeated declaration
+is unresolved and validation fails closed.
+
 An atom that is exactly `#<item-id>` (optionally followed by one terminal `.`
 or `!`) resolves an exact-case item id before case-folded ids or aliases.
 Formatting or list-marker prefixes do not participate in that identity rule.

skills/run-with-first-tree/scripts/build_local_work_graph.py

@@ -372,6 +372,10 @@ def identity_syntax_is_valid(original: str, reference_id: str) -> bool:
             f"{UNRESOLVED_DEPENDENCY_PREFIX}oversized-blocker-value:{size}"
             for size in oversized_blocker_sizes
         ]
+        if blocker_declaration_count == 0:
+            resolved.append(
+                f"{UNRESOLVED_DEPENDENCY_PREFIX}missing-blocked-by-declaration"
+            )
         for original_blocker, blocker, syntax_valid in raw_blockers:
             identity_candidates = [blocker]
             if blocker.endswith((".", "!")):

skills/run-with-first-tree/scripts/validate_work_graph.py

@@ -43,8 +43,11 @@ def _load_manifest(path: Path) -> tuple[dict[str, Any] | None, list[str]]:
 
 def _validate_shape(manifest: dict[str, Any]) -> list[str]:
     errors: list[str] = []
-    if manifest.get("schema_version") != 1:
-        errors.append("schema_version must be 1")
+    if (
+        type(manifest.get("schema_version")) is not int
+        or manifest.get("schema_version") != 1
+    ):
+        errors.append("schema_version must be the integer 1")
 
     source = manifest.get("source")
     if not isinstance(source, dict):
@@ -77,6 +80,13 @@ def _validate_shape(manifest: dict[str, Any]) -> list[str]:
             elif not isinstance(item[field], expected_type):
                 errors.append(f"{prefix}.{field} must be {expected_type.__name__}")
 
+        title = item.get("title")
+        if isinstance(title, str) and not title.strip():
+            errors.append(f"{prefix}.title must be a non-empty string")
+        source_reference = item.get("source")
+        if isinstance(source_reference, str) and not source_reference.strip():
+            errors.append(f"{prefix}.source must be a non-empty string")
+
         item_id = item.get("id")
         if isinstance(item_id, str):
             if not item_id.strip():