diff --git a/CHANGELOG.md b/CHANGELOG.md
index d0f1c35..b2a9e38 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,12 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 ### Removed
 - **`repo-finder`'s Category Preference Order and its `3e` category bonus (10%).** With filtering server-side, every candidate matches the user's filters by construction, so a bonus for matching is a constant added to every row and ranks nothing. Its weight went to signals that discriminate: responsiveness 30 → **35%**, outside-contributor track 20 → **25%**.
 
+### Fixed
+- **A `preferences.md` with no `## Filters` block no longer dead-ends the scan.** A file carrying only `## Notes` (or an empty `## Filters` block) compiled to a catch-all and aborted `repo-finder` with `exit 10` and a misleading "`topics: any` with no languages" error the user never wrote — leaving `/contribute` with an empty shortlist. Such a file now means "default filters, plus advisory notes" and falls back to `DEFAULT_PROFILE`. A `## Filters` block with a real typo (`langauges: go`) still fails loudly, so the fallback never swallows a malformed filter. New `prefs_has_filters` helper in `scripts/lib/preferences.sh`; covered by `test_build_queries.sh`.
+- **`/repo-finder` overrides now inherit saved axes from a non-canonical `## filters` header.** The override path (`--lang`/`--topic`/`--min-stars`) read the saved profile with an exact, case-sensitive `## Filters` matcher while `preferences.sh` accepts `## filters` and spacing variants — so `/repo-finder --topic cli` on a hand-edited lowercase-header profile silently dropped the saved `languages`/`stars` and searched with defaults. Both readers now use the same detector. Covered by the new `test_repo_finder_override_inherit.sh`.
+- **The `## Filters` header is matched fully case-insensitively (`tolower`), in both readers.** Previously only `Filters`/`filters` were recognized; a `## FILTERS` block was silently ignored — and with the notes-only fallback above, that meant it emitted the default profile and dropped the user's filters with no error. `scripts/lib/preferences.sh` and the `/repo-finder` override path now normalize the header the same way.
+- **An override that inherits from a malformed saved profile now fails loudly.** The override extraction greps the saved block for exact keys (`languages:`), so a mistyped `langauges: go` — which the normal path rejects with `exit 10` — was silently dropped, letting an override run proceed on a broken profile. When any axis is inherited, the saved profile is now validated with the same compiler the normal path uses (a full `--lang/--topic/--min-stars` override skips the check, since it reads nothing from the saved file).
+
 ## [0.6.4] — 2026-07-13
 
 ## [0.6.3] — 2026-07-12
diff --git a/commands/repo-finder.md b/commands/repo-finder.md
index c17efcb..bd8b3c2 100644
--- a/commands/repo-finder.md
+++ b/commands/repo-finder.md
@@ -111,12 +111,31 @@ if [ -n "$LANGS$TOPICS$MIN_STARS" ]; then
   # fire the moment this block ends.
   OVERRIDE=$(mktemp "${TMPDIR:-/tmp}/superhuman-prefs.XXXXXX") || { echo "mktemp failed"; exit 1; }
 
+  # If any axis is inherited from the saved profile, that profile must itself be
+  # valid. A malformed saved line (e.g. `langauges: go`) is caught on the normal
+  # /repo-finder path but would be silently dropped by the key-specific extraction
+  # below, letting an override bypass the fail-loud contract. Validate with the
+  # same compiler the normal path uses — but only when something is actually
+  # inherited (a full --lang/--topic/--min-stars override never reads it).
+  if [ -f "$SAVED" ] && { [ -z "$LANGS" ] || [ -z "$TOPICS" ] || [ -z "$MIN_STARS" ]; } \
+     && ! "${CLAUDE_PLUGIN_ROOT}/scripts/repo-finder/build_queries.sh" --file "$SAVED" --no-nudge >/dev/null 2>&1; then
+    echo "Saved ~/.superhuman/preferences.md is malformed; fix it or run /preferences (an override inherits the axes it doesn't name)."
+    rm -f "$OVERRIDE"; exit 1
+  fi
+
   # Inherit each unnamed axis from the saved profile, so --lang rust on a
   # backend-topics profile still searches backend. Read only the `## Filters` block:
   # a `## Notes` line that happens to begin `languages:`/`topics:`/`stars:` (copied
   # prose) must never be mistaken for a hard filter.
   FILTERS=""
-  [ -f "$SAVED" ] && FILTERS=$(awk '/^## Filters/{f=1;next} /^## /{f=0} f' "$SAVED")
+  # Detect the block with the SAME matcher scripts/lib/preferences.sh uses
+  # (case-insensitive via tolower, spacing-tolerant). A divergent reader silently
+  # fails to inherit saved axes on a '## filters'/'## FILTERS' file and searches
+  # with defaults instead — the silent-wrong-result this whole feature guards against.
+  [ -f "$SAVED" ] && FILTERS=$(awk '
+    /^##[ \t]+/ { f = (tolower($0) ~ /^##[ \t]*filters[ \t]*$/); next }
+    f
+  ' "$SAVED")
   if [ -z "$LANGS" ]; then
     LANGS=$(printf '%s\n' "$FILTERS" | sed -n 's/^[[:space:]]*languages:[[:space:]]*//p' | head -1)
   fi
diff --git a/scripts/lib/preferences.sh b/scripts/lib/preferences.sh
index 3910fed..41d82b0 100644
--- a/scripts/lib/preferences.sh
+++ b/scripts/lib/preferences.sh
@@ -30,7 +30,7 @@ prefs_path() {
 # block that is not `key: value` is an error, not prose — prose belongs in Notes.
 _prefs_filter_lines() {
   awk '
-    /^##[ \t]+/ { inblk = ($0 ~ /^##[ \t]*[Ff]ilters[ \t]*$/); next }
+    /^##[ \t]+/ { inblk = (tolower($0) ~ /^##[ \t]*filters[ \t]*$/); next }
     !inblk      { next }
     /^[ \t]*$/  { next }
     /^[ \t]*#/  { next }
@@ -48,6 +48,17 @@ _prefs_filter_lines() {
   ' "$1"
 }
 
+# True when the file declares a `## Filters` block with at least one content line
+# — i.e. `_prefs_filter_lines` would emit something. A file with only `## Notes`,
+# or an empty `## Filters` block, emits nothing: that is "use the default
+# filters", not a catch-all to reject, so callers fall back to DEFAULT_PROFILE
+# rather than aborting. A malformed line is still content (it emits an `ERR` or a
+# bad-key row), so `langauges: go` stays a loud parse error — the fallback can
+# never silently swallow a typo'd filter.
+prefs_has_filters() {
+  [ -n "$(_prefs_filter_lines "${1:-$(prefs_path)}")" ]
+}
+
 # Comma-separated list -> one trimmed entry per line. Whitespace inside an entry
 # is preserved on purpose; the charset guards below reject it.
 _prefs_split() {
diff --git a/scripts/repo-finder/build_queries.sh b/scripts/repo-finder/build_queries.sh
index 747521f..3ff6d58 100755
--- a/scripts/repo-finder/build_queries.sh
+++ b/scripts/repo-finder/build_queries.sh
@@ -121,7 +121,12 @@ nudge_once() {
   fi
 }
 
-if [ ! -f "$PREFS" ]; then
+# A file that exists but declares no ## Filters content (only ## Notes, or an
+# empty block) means "default filters, plus advisory notes" — not a catch-all to
+# reject. Fall back to DEFAULT_PROFILE. A block WITH content still goes to the
+# parser below, which fails loud on a typo, so this never swallows a malformed
+# filter (see the notes-only + malformed-abort cases in test_build_queries.sh).
+if [ ! -f "$PREFS" ] || ! prefs_has_filters "$PREFS"; then
   nudge_once
   while IFS= read -r q; do
     [ -n "$q" ] && emit "$q"
diff --git a/tests/scripts/test_build_queries.sh b/tests/scripts/test_build_queries.sh
index 20f1adf..1a2a465 100644
--- a/tests/scripts/test_build_queries.sh
+++ b/tests/scripts/test_build_queries.sh
@@ -227,6 +227,50 @@ bash "$BUILD" --file "$tmpdir/bad.md" --no-nudge >/dev/null 2>&1
 rc=$?
 [ "$rc" = "10" ] || fail "malformed preferences must exit 10, got $rc (never fall back to defaults)"
 
+# ---------------------------------------------------------------------------
+# A file with no ## Filters CONTENT is "default filters + advisory notes", NOT a
+# catch-all to reject. It must fall back to DEFAULT_PROFILE, never abort with the
+# misleading 'topics: any with no languages' error the user never wrote. The
+# malformed-abort test above guards the other direction: a Filters block WITH a
+# bad line still exits 10, so the fallback can never swallow a real typo.
+# ---------------------------------------------------------------------------
+
+# 12. Notes-only file (no ## Filters block at all) => DEFAULT_PROFILE, exit 0.
+write notes_only <<'EOF'
+## Notes
+Prefer small, focused libraries. I'd rather fix bugs than add features.
+EOF
+run notes_only > "$tmpdir/notes_only.txt" \
+  || fail "notes-only preferences.md aborted the scan instead of using defaults"
+diff -u "$GOLDEN" "$tmpdir/notes_only.txt" \
+  || fail "notes-only file did not fall back to the default profile"
+
+# 12a. An empty ## Filters block (header, no filter lines) is also 'nothing
+# specified' => DEFAULT_PROFILE, not a catch-all abort.
+write empty_filters <<'EOF'
+## Filters
+
+## Notes
+just some guidance
+EOF
+run empty_filters > "$tmpdir/empty_filters.txt" \
+  || fail "empty ## Filters block aborted the scan instead of using defaults"
+diff -u "$GOLDEN" "$tmpdir/empty_filters.txt" \
+  || fail "empty ## Filters block did not fall back to the default profile"
+
+# 12b. The header is matched case-INSENSITIVELY, not just 'Filters'/'filters'. A
+# '## FILTERS' block must be read as a real filter, never silently ignored —
+# which, combined with the fallback above, would emit the DEFAULT profile and
+# drop the user's filters with no error at all.
+write upper_header <<'EOF'
+## FILTERS
+languages: go
+topics: backend
+stars: 2000
+EOF
+[ "$(run upper_header)" = "language:go topic:backend stars:>2000 archived:false" ] \
+  || fail "'## FILTERS' not recognized as a Filters block: got '$(run upper_header)'"
+
 # 11. Determinism: same profile, two runs, byte-identical output.
 [ "$(run cross3)" = "$(run cross3)" ] || fail "build is not deterministic"
 
diff --git a/tests/scripts/test_repo_finder_override_inherit.sh b/tests/scripts/test_repo_finder_override_inherit.sh
new file mode 100755
index 0000000..b4daf3c
--- /dev/null
+++ b/tests/scripts/test_repo_finder_override_inherit.sh
@@ -0,0 +1,82 @@
+#!/usr/bin/env bash
+# The /repo-finder override path (`--lang`/`--topic`/`--min-stars`) inherits the
+# axes it does NOT name from the saved profile. Two contracts:
+#
+#   1. It reads the saved `## Filters` block with the SAME detector
+#      scripts/lib/preferences.sh uses (case-insensitive, spacing-tolerant). A
+#      divergent matcher silently fails to inherit on a '## filters' file and
+#      searches with defaults instead.
+#   2. When it inherits from the saved profile, that profile must be VALID. A
+#      malformed saved line (`langauges: go`) is caught on the normal path but
+#      would be silently dropped by the key-specific extraction — an override run
+#      must not bypass the fail-loud contract.
+#
+# Network-free, bash 3.2-clean.
+set -euo pipefail
+
+ROOT="${CLAUDE_PLUGIN_ROOT:-$(CDPATH= cd -- "$(dirname -- "$0")/../.." && pwd)}"
+export CLAUDE_PLUGIN_ROOT="$ROOT"
+CMD="$ROOT/commands/repo-finder.md"
+TMP=$(mktemp -d); trap 'rm -rf "$TMP"' EXIT
+HOME="$TMP/home"; export HOME
+mkdir -p "$HOME/.superhuman"
+
+fail() { echo "FAIL: $*"; exit 1; }
+
+# The override block is the 2nd ```bash fence in the command file.
+extract_block2() {
+  awk '/^```bash$/{n++; if(n==2){inb=1; next}} /^```$/{inb=0} inb' "$CMD"
+}
+
+# run_override <saved-content> <LANGS> <TOPICS> <MIN_STARS>
+#   Writes the saved profile, drives the override block with the given axes, and
+#   prints the block's output (including the compiled $OVERRIDE file on success).
+#   Returns the block's exit code.
+run_override() {
+  printf '%s' "$1" > "$HOME/.superhuman/preferences.md"
+  {
+    printf 'LANGS=%q\nTOPICS=%q\nMIN_STARS=%q\n' "$2" "$3" "$4"
+    extract_block2
+    printf 'echo "---OVERRIDE-FILE---"; cat "$OVERRIDE" 2>/dev/null\n'
+  } > "$TMP/block.sh"
+  bash "$TMP/block.sh" 2>&1
+}
+
+# --- Contract 1: inherit unnamed axes from a NON-canonical (lowercase) header. --
+SAVED_LC='## filters
+languages: go
+topics: backend
+stars: 3000
+'
+OUT=$(run_override "$SAVED_LC" "" "cli" "") || fail "override on a valid profile errored: $OUT"
+case "$OUT" in *"languages: go"*)   ;; *) fail "saved 'languages: go' not inherited from '## filters':
+$OUT" ;; esac
+case "$OUT" in *"stars: 3000"*)     ;; *) fail "saved 'stars: 3000' not inherited (fell back to 2000 default):
+$OUT" ;; esac
+case "$OUT" in *"topics: cli"*)     ;; *) fail "--topic override not applied:
+$OUT" ;; esac
+
+# --- Contract 2: a MALFORMED saved profile must fail loud when inherited. -------
+# `langauges` (typo) is not `languages:`, so the key-specific extraction drops it
+# silently; without validation the override would proceed with a broken profile.
+SAVED_BAD='## Filters
+langauges: go
+topics: backend
+'
+set +e
+OUT=$(run_override "$SAVED_BAD" "" "cli" ""); RC=$?
+set -e
+[ "$RC" -ne 0 ] || fail "an override that inherits from a MALFORMED saved profile must fail loud, got exit 0:
+$OUT"
+case "$OUT" in *[Mm]alformed*|*"/preferences"*) ;; *) fail "malformed-saved failure lacked an actionable message:
+$OUT" ;; esac
+
+# --- Contract 2, negative: a FULL override never reads the saved profile, so a --
+# malformed saved file must NOT block it (nothing is inherited). ---------------
+OUT=$(run_override "$SAVED_BAD" "rust" "cli" "500") \
+  || fail "a full --lang/--topic/--min-stars override must not be blocked by a malformed saved profile:
+$OUT"
+case "$OUT" in *"language:rust topic:cli stars:>500"*) ;; *) fail "full override did not compile as given:
+$OUT" ;; esac
+
+echo "OK test_repo_finder_override_inherit.sh"