diff --git a/scripts/check-queue-front-matter.sh b/scripts/check-queue-front-matter.sh
new file mode 100755
index 0000000000..7c83791976
--- /dev/null
+++ b/scripts/check-queue-front-matter.sh
@@ -0,0 +1,114 @@
+#!/usr/bin/env bash
+# Consumer-side front-matter validator for file-based markdown handoff queues
+# (one item per file with YAML front matter). Detects malformed items that make
+# a `grep '^status:'` reconciliation report a false all-clear (#1647).
+#
+#   scripts/check-queue-front-matter.sh <queue-dir>
+#
+# Not a CI gate — the queue lives outside the repository. Invoke at claim time
+# when an agent decides whether work is present.
+#
+# Exit 0 = every item file conforms; 1 = one or more violations; 2 = usage error.
+set -euo pipefail
+
+usage() {
+  printf 'usage: check-queue-front-matter.sh <queue-dir>\n' >&2
+  exit 2
+}
+
+[[ $# -eq 1 ]] || usage
+QUEUE_DIR="$1"
+
+if [[ ! -d "$QUEUE_DIR" ]]; then
+  printf 'Error: queue directory not found: %s\n' "$QUEUE_DIR" >&2
+  exit 2
+fi
+
+VALID_STATUSES='unclaimed|claimed|in-progress|blocked|done'
+VALID_PRIORITIES='low|medium|high|urgent'
+REQUIRED_KEYS=(id title status created producer)
+
+errors=0
+file_count=0
+parsed_count=0
+
+report_violation() {
+  printf 'VIOLATION: %s — %s\n' "$1" "$2"
+  errors=$((errors + 1))
+}
+
+# extract_front_matter <file> — prints front matter body or nothing.
+extract_front_matter() {
+  awk '
+    NR == 1 && $0 == "---" { in_fm = 1; next }
+    in_fm && $0 == "---" { exit }
+    in_fm { print }
+  ' "$1"
+}
+
+# fm_value <front_matter> <key>
+fm_value() {
+  awk -v key="$2" '
+    $1 == key ":" {
+      sub(/^[^:]*:[[:space:]]*/, "")
+      print
+      exit
+    }
+  ' <<<"$1"
+}
+
+for item in "$QUEUE_DIR"/*.md; do
+  [[ -e "$item" ]] || continue
+  base="$(basename "$item")"
+  [[ "$base" == README.md ]] && continue
+  file_count=$((file_count + 1))
+  stem="${base%.md}"
+  fm="$(extract_front_matter "$item")"
+  if [[ -z "${fm//[[:space:]]/}" ]]; then
+    report_violation "$item" 'missing or empty YAML front matter'
+    continue
+  fi
+  parsed_count=$((parsed_count + 1))
+
+  for key in "${REQUIRED_KEYS[@]}"; do
+    val="$(fm_value "$fm" "$key")"
+    if [[ -z "${val//[[:space:]]/}" ]]; then
+      report_violation "$item" "missing required key: $key"
+    fi
+  done
+
+  status="$(fm_value "$fm" status)"
+  if [[ -n "$status" ]]; then
+    if ! grep -qE "^(${VALID_STATUSES})$" <<<"$status"; then
+      report_violation "$item" "status '$status' not in documented set (unclaimed|claimed|in-progress|blocked|done)"
+    fi
+  fi
+
+  priority="$(fm_value "$fm" priority)"
+  if [[ -n "${priority//[[:space:]]/}" ]]; then
+    if ! grep -qE "^(${VALID_PRIORITIES})$" <<<"$priority"; then
+      report_violation "$item" "priority '$priority' not in documented set (low|medium|high|urgent)"
+    fi
+  fi
+
+  id="$(fm_value "$fm" id)"
+  if [[ -n "$id" && "$id" != "$stem" ]]; then
+    report_violation "$item" "id '$id' does not match filename stem '$stem'"
+  fi
+done
+
+printf 'Reconciliation: %d item file(s), %d with parseable front matter\n' \
+  "$file_count" "$parsed_count"
+
+if ((file_count != parsed_count)); then
+  report_violation "$QUEUE_DIR" \
+    "count gap — $((file_count - parsed_count)) file(s) lack parseable front matter (never reconcile by status grep alone)"
+fi
+
+if ((errors > 0)); then
+  printf '\n%d violation(s).\n' "$errors" >&2
+  exit 1
+fi
+
+echo "Queue front matter OK."
+exit 0
diff --git a/scripts/check-queue-front-matter.test.sh b/scripts/check-queue-front-matter.test.sh
new file mode 100755
index 0000000000..3fe66ce51e
--- /dev/null
+++ b/scripts/check-queue-front-matter.test.sh
@@ -0,0 +1,107 @@
+#!/usr/bin/env bash
+# Unit tests for check-queue-front-matter.sh.
+set -uo pipefail
+
+SELF_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+SCRIPT="$SELF_DIR/check-queue-front-matter.sh"
+
+PASS=0
+FAIL=0
+fail() {
+  echo "FAIL: $*" >&2
+  FAIL=$((FAIL + 1))
+}
+ok() {
+  echo "ok: $*"
+  PASS=$((PASS + 1))
+}
+
+new_queue() {
+  mktemp -d
+}
+
+run_check() (
+  bash "$SCRIPT" "$1"
+)
+
+# --- valid item passes -------------------------------------------------------
+q="$(new_queue)"
+cat >"$q/20260812-sample.md" <<'EOF'
+---
+id: 20260812-sample
+title: Sample item
+status: unclaimed
+created: 2026-08-12T12:00:00Z
+producer: test-fixture
+---
+Body
+EOF
+if run_check "$q" >/dev/null 2>&1; then
+  ok "valid item passes"
+else
+  fail "valid item should pass"
+fi
+
+# --- missing front matter fails ----------------------------------------------
+q="$(new_queue)"
+printf 'No front matter here\n' >"$q/20260812-bad.md"
+if run_check "$q" >/dev/null 2>&1; then
+  fail "missing front matter should fail"
+else
+  ok "missing front matter fails"
+fi
+
+# --- invalid status fails ----------------------------------------------------
+q="$(new_queue)"
+cat >"$q/20260812-open.md" <<'EOF'
+---
+id: 20260812-open
+title: Bad status
+status: open
+created: 2026-08-12T12:00:00Z
+producer: test-fixture
+---
+EOF
+if run_check "$q" >/dev/null 2>&1; then
+  fail "invalid status should fail"
+else
+  ok "invalid status fails"
+fi
+
+# --- id stem mismatch fails --------------------------------------------------
+q="$(new_queue)"
+cat >"$q/20260812-wrong.md" <<'EOF'
+---
+id: other-id
+title: Mismatch
+status: unclaimed
+created: 2026-08-12T12:00:00Z
+producer: test-fixture
+---
+EOF
+if run_check "$q" >/dev/null 2>&1; then
+  fail "id/filename mismatch should fail"
+else
+  ok "id stem mismatch fails"
+fi
+
+# --- README.md is ignored ----------------------------------------------------
+q="$(new_queue)"
+printf '# readme\n' >"$q/README.md"
+cat >"$q/20260812-only.md" <<'EOF'
+---
+id: 20260812-only
+title: Only item
+status: done
+created: 2026-08-12T12:00:00Z
+producer: test-fixture
+---
+EOF
+if run_check "$q" >/dev/null 2>&1; then
+  ok "README.md ignored"
+else
+  fail "README should be ignored: valid sole item should pass"
+fi
+
+printf '\n%d passed, %d failed\n' "$PASS" "$FAIL"
+[[ "$FAIL" -eq 0 ]]