diff --git a/.agents/pm/history/pm-github-wb4q.jsonl b/.agents/pm/history/pm-github-wb4q.jsonl
new file mode 100644
index 00000000..a780a109
--- /dev/null
+++ b/.agents/pm/history/pm-github-wb4q.jsonl
@@ -0,0 +1,8 @@
+{"ts":"2026-08-10T05:53:22.197Z","author":"pi-agent","author_source":"asserted","agent_harness":"pi","agent_model":"glm-5.2:cloud","agent_model_source":"environment","agent_instance":"07e97aa365b211e55b7745cd","agent_provenance":{"model":{"value":"glm-5.2:cloud","source":"environment"},"effort":null,"role":null,"topic":null},"op":"create","patch":[{"op":"add","path":"/metadata/id","value":"pm-github-wb4q"},{"op":"add","path":"/metadata/title","value":"Propagate the docstring gate entry guard fix"},{"op":"add","path":"/metadata/description","value":"The isMainInvocation guard caught realpathSync errors and returned false, causing npm run docstring to exit 0 having scanned nothing — a mandatory release gate reporting success without doing its job. The guard now propagates the error so a broken environment fails loudly instead of silently passing the gate."},{"op":"add","path":"/metadata/type","value":"Issue"},{"op":"add","path":"/metadata/status","value":"open"},{"op":"add","path":"/metadata/priority","value":2},{"op":"add","path":"/metadata/tags","value":["docstrings","gate"]},{"op":"add","path":"/metadata/created_at","value":"2026-08-10T05:53:22.197Z"},{"op":"add","path":"/metadata/updated_at","value":"2026-08-10T05:53:22.197Z"},{"op":"add","path":"/metadata/author","value":"pi-agent"}],"before_hash":"3cc22dff72be7b14824654a7a64ea62b04799939b2fee54c1b5f52ca60bf6df0","after_hash":"3b4a129ab17ce32fba14a15db02676d081d6db922aeb740949056f7d428207ca","message":""}
+{"ts":"2026-08-10T05:53:25.011Z","author":"pi-agent","author_source":"asserted","agent_harness":"pi","agent_model":"glm-5.2:cloud","agent_model_source":"environment","agent_instance":"07e97aa365b211e55b7745cd","agent_provenance":{"model":{"value":"glm-5.2:cloud","source":"environment"},"effort":null,"role":null,"topic":null},"op":"note_add","patch":[{"op":"replace","path":"/metadata/updated_at","value":"2026-08-10T05:53:25.011Z"},{"op":"add","path":"/metadata/notes","value":[{"created_at":"2026-08-10T05:53:25.011Z","author":"pi-agent","text":"The isMainInvocation function in scripts/docstring-gate.ts wrapped realpathSync in a try/catch that returned false on ENOENT. When argv[1] could not be resolved, the top-level selector called the no-op placeholder instead of main, so npm run docstring exited 0 having scanned nothing. A required release check reported success without doing its job. The corrected implementation propagates the realpathSync error: a broken environment must not silently satisfy a gate."}]}],"before_hash":"3b4a129ab17ce32fba14a15db02676d081d6db922aeb740949056f7d428207ca","after_hash":"4a5d9d1e7a163fa42883a5b5430a0effb5e995fa19a7ec497e499f16a16aaff4"}
+{"ts":"2026-08-10T05:53:28.150Z","author":"pi-agent","author_source":"asserted","agent_harness":"pi","agent_model":"glm-5.2:cloud","agent_model_source":"environment","agent_instance":"07e97aa365b211e55b7745cd","agent_provenance":{"model":{"value":"glm-5.2:cloud","source":"environment"},"effort":null,"role":null,"topic":null},"op":"comment_add","patch":[{"op":"replace","path":"/metadata/updated_at","value":"2026-08-10T05:53:28.150Z"},{"op":"add","path":"/metadata/comments","value":[{"created_at":"2026-08-10T05:53:28.150Z","author":"pi-agent","text":"Verified: node --experimental-strip-types -e with an unresolvable argv[1] now throws ENOENT instead of returning false. The gate fails loudly."}]}],"before_hash":"4a5d9d1e7a163fa42883a5b5430a0effb5e995fa19a7ec497e499f16a16aaff4","after_hash":"406c4c1b68a25f9dd96ad864e292e911d1a8f3afe9ad625bcde33ed6ef19a161"}
+{"ts":"2026-08-10T05:53:28.694Z","author":"pi-agent","author_source":"asserted","agent_harness":"pi","agent_model":"glm-5.2:cloud","agent_model_source":"environment","agent_instance":"07e97aa365b211e55b7745cd","agent_provenance":{"model":{"value":"glm-5.2:cloud","source":"environment"},"effort":null,"role":null,"topic":null},"op":"files_add","patch":[{"op":"replace","path":"/metadata/updated_at","value":"2026-08-10T05:53:28.694Z"},{"op":"add","path":"/metadata/files","value":[{"path":"scripts/docstring-gate.ts","scope":"project"}]}],"before_hash":"406c4c1b68a25f9dd96ad864e292e911d1a8f3afe9ad625bcde33ed6ef19a161","after_hash":"772b1cced4d577af1270e47b6682715476c30da4d6a3364a4f9e68db7cdd918a"}
+{"ts":"2026-08-10T05:53:29.231Z","author":"pi-agent","author_source":"asserted","agent_harness":"pi","agent_model":"glm-5.2:cloud","agent_model_source":"environment","agent_instance":"07e97aa365b211e55b7745cd","agent_provenance":{"model":{"value":"glm-5.2:cloud","source":"environment"},"effort":null,"role":null,"topic":null},"op":"files_add","patch":[{"op":"add","path":"/metadata/files/1","value":{"path":"test/docstring-gate.test.ts","scope":"project"}},{"op":"replace","path":"/metadata/updated_at","value":"2026-08-10T05:53:29.231Z"}],"before_hash":"772b1cced4d577af1270e47b6682715476c30da4d6a3364a4f9e68db7cdd918a","after_hash":"255dd7333a675d613c172ecbba4199926ffecfcd9d14ed340c03364565049eae"}
+{"ts":"2026-08-10T05:53:31.847Z","author":"pi-agent","author_source":"asserted","agent_harness":"pi","agent_model":"glm-5.2:cloud","agent_model_source":"environment","agent_instance":"07e97aa365b211e55b7745cd","agent_provenance":{"model":{"value":"glm-5.2:cloud","source":"environment"},"effort":null,"role":null,"topic":null},"op":"close","patch":[{"op":"replace","path":"/metadata/updated_at","value":"2026-08-10T05:53:31.847Z"},{"op":"replace","path":"/metadata/status","value":"closed"},{"op":"add","path":"/metadata/closed_at","value":"2026-08-10T05:53:31.831Z"},{"op":"add","path":"/metadata/completed_at","value":"2026-08-10T05:53:31.831Z"},{"op":"add","path":"/metadata/resolution","value":"isMainInvocation propagates realpathSync errors instead of catching them and returning false"},{"op":"add","path":"/metadata/expected_result","value":"npm run docstring with an unresolvable argv[1] throws ENOENT and exits non-zero"},{"op":"add","path":"/metadata/actual_result","value":"npm run docstring with an unresolvable argv[1] previously exited 0 having scanned nothing"},{"op":"add","path":"/metadata/close_reason","value":"fixed"}],"before_hash":"255dd7333a675d613c172ecbba4199926ffecfcd9d14ed340c03364565049eae","after_hash":"4420083076a9c9d945f70124062a52b71d59591a68bcb4a1c412809feff5834e"}
+{"ts":"2026-08-10T06:31:01.671Z","author":"pi-agent","author_source":"asserted","agent_harness":"pi","agent_model":"glm-5.2:cloud","agent_model_source":"environment","agent_instance":"7525f7064349b35d9826cadf","agent_provenance":{"model":{"value":"glm-5.2:cloud","source":"environment"},"effort":null,"role":null,"topic":null},"op":"note_add","patch":[{"op":"add","path":"/metadata/notes/1","value":{"created_at":"2026-08-10T06:31:01.671Z","author":"pi-agent","text":"Greptile (P2 on pm-beads) and CodeRabbit (Major on pm-slack) independently flagged the one-sided comparison in isMainInvocation: pathToFileURL(realpathSync(entry)).href === moduleUrl resolves only argv[1], leaving moduleUrl holding the symlink under --preserve-symlinks. Canonicalising both sides through realpathSync fixes it. Verified by measurement: with moduleUrl holding the symlink path, both-sides (new) returns true while one-sided (old) returns false."}},{"op":"replace","path":"/metadata/updated_at","value":"2026-08-10T06:31:01.671Z"}],"before_hash":"4420083076a9c9d945f70124062a52b71d59591a68bcb4a1c412809feff5834e","after_hash":"6d0e30e9f5a61f6cc2e420a7c0ab3685a582da62c6c265360f001c9f441989bd"}
+{"ts":"2026-08-10T07:08:43.529Z","author":"pi-agent","author_source":"asserted","agent_harness":"pi","agent_model":"glm-5.2:cloud","agent_model_source":"environment","agent_instance":"1684e74de48dd9cf0e628b6d","agent_provenance":{"model":{"value":"glm-5.2:cloud","source":"environment"},"effort":null,"role":null,"topic":null},"op":"note_add","patch":[{"op":"add","path":"/metadata/notes/2","value":{"created_at":"2026-08-10T07:08:43.529Z","author":"pi-agent","text":"The previous test (isMainInvocation resolves matching and non-matching scripts) did not use symlinks at all, so it could not distinguish the fixed implementation from the broken one. Added a new test (canonicalizes a symlinked moduleUrl, as --preserve-symlinks produces) that puts the symlink in moduleUrl (pathToFileURL(link).href), which is what Node records in import.meta.url under --preserve-symlinks. Verified by measurement: reverting to the old one-sided comparison makes the new test fail (fail 1), restoring the canonicalization makes it pass (fail 0)."}},{"op":"replace","path":"/metadata/updated_at","value":"2026-08-10T07:08:43.529Z"}],"before_hash":"6d0e30e9f5a61f6cc2e420a7c0ab3685a582da62c6c265360f001c9f441989bd","after_hash":"fd43aeb95b4c42c1cd383665f3540613408c2a72ee07b884cf762645b296c485"}
diff --git a/.agents/pm/issues/pm-github-wb4q.toon b/.agents/pm/issues/pm-github-wb4q.toon
new file mode 100644
index 00000000..1a9c5ce1
--- /dev/null
+++ b/.agents/pm/issues/pm-github-wb4q.toon
@@ -0,0 +1,26 @@
+id: pm-github-wb4q
+title: Propagate the docstring gate entry guard fix
+description: "The isMainInvocation guard caught realpathSync errors and returned false, causing npm run docstring to exit 0 having scanned nothing — a mandatory release gate reporting success without doing its job. The guard now propagates the error so a broken environment fails loudly instead of silently passing the gate."
+type: Issue
+status: closed
+priority: 2
+tags[2]: docstrings,gate
+created_at: "2026-08-10T05:53:22.197Z"
+updated_at: "2026-08-10T07:08:43.529Z"
+closed_at: "2026-08-10T05:53:31.831Z"
+completed_at: "2026-08-10T05:53:31.831Z"
+author: pi-agent
+resolution: isMainInvocation propagates realpathSync errors instead of catching them and returning false
+expected_result: "npm run docstring with an unresolvable argv[1] throws ENOENT and exits non-zero"
+actual_result: "npm run docstring with an unresolvable argv[1] previously exited 0 having scanned nothing"
+comments[1]{created_at,author,text}:
+  "2026-08-10T05:53:28.150Z",pi-agent,"Verified: node --experimental-strip-types -e with an unresolvable argv[1] now throws ENOENT instead of returning false. The gate fails loudly."
+notes[3]{created_at,author,text}:
+  "2026-08-10T05:53:25.011Z",pi-agent,"The isMainInvocation function in scripts/docstring-gate.ts wrapped realpathSync in a try/catch that returned false on ENOENT. When argv[1] could not be resolved, the top-level selector called the no-op placeholder instead of main, so npm run docstring exited 0 having scanned nothing. A required release check reported success without doing its job. The corrected implementation propagates the realpathSync error: a broken environment must not silently satisfy a gate."
+  "2026-08-10T06:31:01.671Z",pi-agent,"Greptile (P2 on pm-beads) and CodeRabbit (Major on pm-slack) independently flagged the one-sided comparison in isMainInvocation: pathToFileURL(realpathSync(entry)).href === moduleUrl resolves only argv[1], leaving moduleUrl holding the symlink under --preserve-symlinks. Canonicalising both sides through realpathSync fixes it. Verified by measurement: with moduleUrl holding the symlink path, both-sides (new) returns true while one-sided (old) returns false."
+  "2026-08-10T07:08:43.529Z",pi-agent,"The previous test (isMainInvocation resolves matching and non-matching scripts) did not use symlinks at all, so it could not distinguish the fixed implementation from the broken one. Added a new test (canonicalizes a symlinked moduleUrl, as --preserve-symlinks produces) that puts the symlink in moduleUrl (pathToFileURL(link).href), which is what Node records in import.meta.url under --preserve-symlinks. Verified by measurement: reverting to the old one-sided comparison makes the new test fail (fail 1), restoring the canonicalization makes it pass (fail 0)."
+files[2]{path,scope}:
+  scripts/docstring-gate.ts,project
+  test/docstring-gate.test.ts,project
+close_reason: fixed
+body: ""
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 68593dcd..90b1b61d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,7 @@
 
 ### Fixed
 
+- Propagate the docstring gate entry guard fix ([pm-github-wb4q](https://github.com/unbraind/pm-github/blob/main/.agents/pm/issues/pm-github-wb4q.toon))
 - Converge changelog generation and verification on replace mode ([pm-github-8f60](https://github.com/unbraind/pm-github/blob/main/.agents/pm/issues/pm-github-8f60.toon))
 - The mandatory docstring gate could skip its own scan and still exit zero ([pm-github-wxob](https://github.com/unbraind/pm-github/blob/main/.agents/pm/issues/pm-github-wxob.toon))
 
diff --git a/scripts/docstring-gate.ts b/scripts/docstring-gate.ts
index 5676ba37..541339bc 100644
--- a/scripts/docstring-gate.ts
+++ b/scripts/docstring-gate.ts
@@ -88,39 +88,43 @@ export function main(root: string): void {
 }
 
 /**
- * Whether the script is being invoked directly rather than imported by a test.
+ * Whether this module is the process entry point rather than a test import.
  *
- * Compares resolved real filesystem paths on both sides. `import.meta.url` is
- * already symlink-resolved as a URL, but `argv[1]` may point through a symlink
- * or carry a different drive-letter casing than the URL form, so an exact
- * string comparison would treat a direct invocation as a library import and
- * silently skip {@link main}. Resolving both sides through `realpathSync`
- * removes that ambiguity.
+ * Both sides are canonicalised through `realpathSync` before comparison. A
+ * launcher reaching this file through a symlink (an npm bin shim, a linked
+ * workspace) would otherwise compare unequal and skip the gate silently.
  *
- * The two resolutions fail for opposite reasons and are deliberately not
- * treated alike. An unresolvable `argv[1]` only means the entry point is not
- * this file, which is the ordinary "imported by a test" case, so it answers
- * false. An unresolvable *own* module path is an internal contradiction: this
- * file is executing, so it exists. Swallowing that would leave {@link main}
- * unreached and the process exit code at zero — a mandatory gate reporting
- * success having scanned nothing. It therefore fails closed and throws.
+ * Resolving only `argv[1]` would be enough under Node's defaults, where the
+ * ESM loader realpaths a module before recording `import.meta.url`. It is not
+ * enough under `--preserve-symlinks`/`--preserve-symlinks-main`, which leave
+ * `moduleUrl` holding the symlink while `realpathSync(entry)` resolves it.
+ * The two would then compare unequal on a direct invocation and the gate would
+ * exit 0 without scanning — the exact silent skip this function exists to
+ * prevent, reintroduced by a runtime flag. Canonicalising both sides adds a
+ * second `realpathSync` and removes the dependence on how Node was launched.
  *
- * @param argv - The process argv slice to inspect.
+ * An unresolvable `argv[1]` **propagates** rather than returning false. The two
+ * outcomes are not equally safe: returning false means `npm run docstring`
+ * exits 0 having scanned nothing, which is a required release check reporting
+ * success without doing its job — the one failure this gate exists to prevent.
+ * Letting `realpathSync` throw turns that into a loud non-zero exit. The case
+ * requires `argv[1]` to stop resolving after Node has already loaded this file,
+ * so in practice it means the environment is broken, and a broken environment
+ * must not silently satisfy a gate.
+ *
+ * A genuinely different entry path still returns false, which is how a test
+ * importing this module declines to run the gate.
+ *
+ * @param argv - The process argv to inspect.
  * @param moduleUrl - The `import.meta.url` of the module that might be main.
- * @returns True when `argv[1]` resolves to this module's own real path.
- * @throws If this module's own path cannot be resolved.
+ * @returns True when `argv[1]` and `moduleUrl` canonicalise to the same path,
+ *          false when they canonicalise to different ones.
+ * @throws Whatever `realpathSync` throws when either path cannot be resolved.
  */
 export function isMainInvocation(argv: readonly string[], moduleUrl: string): boolean {
   const entry = argv[1];
   if (entry === undefined) return false;
-  const self = realpathSync(fileURLToPath(moduleUrl));
-  let resolvedEntry: string;
-  try {
-    resolvedEntry = realpathSync(entry);
-  } catch {
-    return false;
-  }
-  return resolvedEntry === self;
+  return realpathSync(entry) === realpathSync(fileURLToPath(moduleUrl));
 }
 
 if (isMainInvocation(process.argv, import.meta.url)) {
diff --git a/test/docstring-gate.test.ts b/test/docstring-gate.test.ts
index 2f656f1f..db19d62c 100644
--- a/test/docstring-gate.test.ts
+++ b/test/docstring-gate.test.ts
@@ -11,7 +11,7 @@
  */
 
 import assert from "node:assert/strict";
-import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from "node:fs";
+import { mkdirSync, mkdtempSync, rmSync, symlinkSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { resolve, join } from "node:path";
 import { pathToFileURL } from "node:url";
@@ -94,29 +94,49 @@ test("docstring gate isMainInvocation resolves matching and non-matching scripts
     assert.equal(isMainInvocation([process.execPath, script], url), true);
     assert.equal(isMainInvocation([process.execPath, other], url), false);
     assert.equal(isMainInvocation([process.execPath], url), false);
-    // An entry path that does not exist is the ordinary "not this script" case.
-    assert.equal(isMainInvocation([process.execPath, join(root, "absent.ts")], url), false);
   } finally {
     rmSync(root, { recursive: true, force: true });
   }
 });
 
-test("docstring gate isMainInvocation fails closed when its own path is unresolvable", () => {
-  // The gate is mandatory, so an unresolvable *own* module path must crash rather
-  // than leave main() unreached with the exit code still at zero — that shape
-  // reports success having scanned nothing. Only the self-resolution throws; an
-  // unresolvable argv[1] stays a plain false, asserted in the test above.
-  const root = mkdtempSync(join(tmpdir(), "pm-github-docstring-self-"));
+test("docstring gate isMainInvocation canonicalizes a symlinked moduleUrl, as --preserve-symlinks produces", () => {
+  // A symlink case that passes argv[1] as the link and moduleUrl as the REAL
+  // path cannot tell the two implementations apart: realpathSync(link) resolves
+  // to the real path, so the old one-sided comparison satisfied it too. This is
+  // the case that can: moduleUrl holds the SYMLINK, which is what Node records
+  // in import.meta.url under --preserve-symlinks / --preserve-symlinks-main.
+  //
+  // Old: pathToFileURL(realpathSync(link)).href === linkUrl -> false, so the
+  // selector calls the placeholder and the gate exits 0 without scanning.
+  // New: realpathSync(link) === realpathSync(fileURLToPath(linkUrl)) -> true.
+  const gatePath = resolve(import.meta.dirname, "..", "scripts", "docstring-gate.ts");
+  const linkDir = mkdtempSync(join(tmpdir(), "pm-github-docgate-preserve-"));
+  const link = join(linkDir, "docstring-gate.ts");
   try {
-    const entry = join(root, "docstring-gate.ts");
-    writeFileSync(entry, "");
-    const absentSelf = pathToFileURL(join(root, "vanished", "docstring-gate.ts")).href;
-    assert.throws(() => isMainInvocation([process.execPath, entry], absentSelf), /ENOENT/);
+    symlinkSync(gatePath, link);
+    assert.equal(
+      isMainInvocation([process.execPath, link], pathToFileURL(link).href),
+      true,
+      "a symlinked moduleUrl must still resolve to a direct invocation",
+    );
   } finally {
-    rmSync(root, { recursive: true, force: true });
+    rmSync(linkDir, { recursive: true, force: true });
   }
 });
 
+test("docstring gate isMainInvocation throws rather than skipping the gate when argv[1] cannot be resolved", () => {
+  const root = resolve(import.meta.dirname, "..");
+  const gateUrl = pathToFileURL(resolve(root, "scripts", "docstring-gate.ts")).href;
+  // Returning false here would leave `npm run docstring` exiting 0 having
+  // scanned nothing - a required release check reporting success without doing
+  // its job. Crashing is the safe outcome, so assert it is what happens.
+  assert.throws(
+    () => isMainInvocation([process.execPath, resolve(root, "does-not-exist.ts")], gateUrl),
+    (error: unknown) => (error as NodeJS.ErrnoException).code === "ENOENT",
+    "an unresolvable entry must propagate, not silently decline to run the gate",
+  );
+});
+
 test("docstring gate main writes a success line to stdout and exits 0", () => {
   // The real repository is fully documented, so main() takes the success path:
   // non-empty stdout is terminated with a newline and exitCode stays 0. This