fix(ci): dedupe @codex only via head-pinned markers

Drop plain-unpinned timestamp heuristics — they cannot safely know which
SHA a bare @codex review targeted. Skip re-request when a trusted author
already pinned this head with cursor-codex-head or cursor-external-codex.

.github/workflows/cursor-automation.yml

@@ -5361,8 +5361,7 @@ jobs:
               },
             );
             const forceRetry =
-              process.env.GITHUB_EVENT_NAME === 'workflow_dispatch';
-            if (
+              process.env.GITHUB_EVENT_NAME === 'workflow_dispatch';            if (
               !forceRetry &&
               auto.shouldSkipExternalCodexRerequest({
                 existingComments: comments,

scripts/cursor-automation.cjs

@@ -1805,18 +1805,80 @@ function buildExternalCodexRerequestComment(headSha) {
   ].join('\n');
 }
 
+/**
+ * True when a comment body is a Codex review *request* (not a clean summary).
+ * Matches "@codex review" as a mention token, not "Codex Review: …" summaries.
+ */
+function isCodexReviewRequestBody(body) {
+  const text = String(body || '');
+  if (!/(^|[^A-Za-z0-9_@])@codex\s+review\b/i.test(text)) return false;
+  // Connector clean/noise posts never use the @codex request form.
+  return true;
+}
+
+/**
+ * Authors whose @codex review posts count for same-head dedupe.
+ * Includes maintainers/GITHUB_TOKEN and Cursor's PR bot (often posts a plain
+ * @codex review before our own_rerequest job lands).
+ */
+function isCodexRequestDedupeAuthor(login, { ownActors } = {}) {
+  if (isTrustedAutomationControlAuthor(login, { ownActors })) return true;
+  const name = String(login || '')
+    .trim()
+    .toLowerCase()
+    .replace(/^@/, '');
+  return name === 'cursor[bot]' || name === 'cursor';
+}
+
+/**
+ * Skip posting another @codex review when this head was already requested.
+ *
+ * Historical bug: only `cursor-external-codex:SHA` counted. Automation
+ * comments that pin `cursor-codex-head:SHA` (and maintainer requests built the
+ * same way) did not, so a second synchronize-path request could fire for the
+ * same SHA while an earlier job was still in flight — clean issue comment from
+ * one job, findings review from the other.
+ *
+ * Skip when a trusted/dedupe author already requested this head via:
+ * - `cursor-external-codex:SHA`, or
+ * - `cursor-codex-head:SHA` pin matching headSha.
+ *
+ * Plain unpinned "@codex review" is intentionally ignored: without a head pin
+ * we cannot tell which SHA it targeted, and timestamp heuristics (age, commit
+ * date, PR.updated_at) all have false-positive races. Prefer always planting
+ * a head pin (buildCodexReviewRequestComment) so re-request is safe.
+ *
+ * `notBefore` is accepted but unused (kept so older workflow callers do not
+ * throw if they still pass it).
+ */
 function shouldSkipExternalCodexRerequest({
   existingComments = [],
   headSha,
   ownActors,
+  notBefore: _notBefore = null,
+  notBeforeSlackMs: _notBeforeSlackMs = 5_000,
 } = {}) {
-  const marker = `<!-- cursor-external-codex:${sanitizeUntrustedText(headSha, 64)} -->`;
-  return existingComments.some(
-    (c) =>
-      isTrustedAutomationControlAuthor(c?.user?.login || c?.login, {
-        ownActors,
-      }) && String(c.body || '').includes(marker),
-  );
+  const want = String(headSha || '')
+    .trim()
+    .toLowerCase();
+  if (!want) return false;
+  const externalMarker = `<!-- cursor-external-codex:${sanitizeUntrustedText(want, 64)} -->`;
+
+  return existingComments.some((c) => {
+    const login = c?.user?.login || c?.login;
+    if (!isCodexRequestDedupeAuthor(login, { ownActors })) return false;
+    const body = String(c?.body || '');
+    if (!isCodexReviewRequestBody(body)) return false;
+
+    // Explicit external marker for this SHA (legacy + current automation).
+    if (body.includes(externalMarker)) return true;
+
+    // Automation / human request that pins this head.
+    const pinned = extractRequestedHeadSha(body);
+    if (pinned && commitShasMatch(want, pinned)) return true;
+
+    return false;
+  });
 }
 
 function buildSlackPayload({

scripts/cursor-automation.test.cjs

@@ -4139,6 +4139,101 @@ test('shouldSkipExternalCodexRerequest matches trusted head sha marker only', ()
   );
 });
 
+test('shouldSkipExternalCodexRerequest honors head pins; ignores plain unpinned @codex', () => {
+  const sha = 'deadbeefcafebabe000000000000000000000001';
+  const short = sha.slice(0, 12);
+  // Automation request with head pin but no external marker still dedupes.
+  assert.equal(
+    auto.shouldSkipExternalCodexRerequest({
+      headSha: sha,
+      ownActors: 'binaricat,netcatty-bot,github-actions[bot]',
+      existingComments: [
+        {
+          user: { login: 'binaricat' },
+          body: auto.buildCodexReviewRequestComment(1, sha),
+        },
+      ],
+    }),
+    true,
+  );
+  // Short SHA pin matches full head.
+  assert.equal(
+    auto.shouldSkipExternalCodexRerequest({
+      headSha: sha,
+      ownActors: 'binaricat',
+      existingComments: [
+        {
+          user: { login: 'binaricat' },
+          body: `<!-- cursor-automation -->\n\n@codex review\n\n<!-- cursor-codex-head:${short} -->`,
+        },
+      ],
+    }),
+    true,
+  );
+  // Plain unpinned @codex never suppresses — cannot know which SHA it meant.
+  assert.equal(
+    auto.shouldSkipExternalCodexRerequest({
+      headSha: sha,
+      ownActors: 'binaricat',
+      notBefore: '2026-08-05T14:00:00Z',
+      existingComments: [
+        {
+          user: { login: 'cursor[bot]' },
+          created_at: '2026-08-05T14:00:30Z',
+          body: '@codex review',
+        },
+      ],
+    }),
+    false,
+  );
+  assert.equal(
+    auto.shouldSkipExternalCodexRerequest({
+      headSha: sha,
+      ownActors: 'binaricat',
+      existingComments: [
+        {
+          user: { login: 'binaricat' },
+          created_at: '2026-08-05T14:00:10Z',
+          body: '@codex review',
+        },
+      ],
+    }),
+    false,
+  );
+  // Connector clean summary is not a request.
+  assert.equal(
+    auto.shouldSkipExternalCodexRerequest({
+      headSha: sha,
+      ownActors: 'binaricat',
+      existingComments: [
+        {
+          user: { login: 'chatgpt-codex-connector[bot]' },
+          created_at: '2026-08-05T14:00:59Z',
+          body: "Codex Review: Didn't find any major issues.\n\n**Reviewed commit:** `deadbeef`",
+        },
+      ],
+    }),
+    false,
+  );
+  // Different head pin does not skip.
+  assert.equal(
+    auto.shouldSkipExternalCodexRerequest({
+      headSha: sha,
+      ownActors: 'binaricat',
+      existingComments: [
+        {
+          user: { login: 'binaricat' },
+          body: auto.buildCodexReviewRequestComment(
+            1,
+            'ffffffffffffffffffffffffffffffffffffffff',
+          ),
+        },
+      ],
+    }),
+    false,
+  );
+});
+
 test('parseCodexReviewOutcome accepts clean reaction without summary text', () => {
   const outcome = auto.parseCodexReviewOutcome({
     summaryText: '',