diff --git a/.claude/skills/verify-open-pstack/SKILL.md b/.claude/skills/verify-open-pstack/SKILL.md
index 46fedffb..4f9dc155 100644
--- a/.claude/skills/verify-open-pstack/SKILL.md
+++ b/.claude/skills/verify-open-pstack/SKILL.md
@@ -99,6 +99,7 @@ Read receipts as data, never shell input. Do not put credentials in prompts or p
 - scripts/provenance.test.ts
 - scripts/provenance.ts
 - scripts/reflect.test.ts
+- scripts/skill-invocation.test.ts
 - scripts/types.ts
 - scripts/verify.sh
 - scripts/verify.test.ts
diff --git a/.claude/skills/verify-open-pstack/features/README.md b/.claude/skills/verify-open-pstack/features/README.md
index 25053d6e..6103cb01 100644
--- a/.claude/skills/verify-open-pstack/features/README.md
+++ b/.claude/skills/verify-open-pstack/features/README.md
@@ -16,6 +16,8 @@ The ownership table below says which features a changed path reaches. `SKILL.md`
 | `project` | Native discovery/invocation of this verifier in both harnesses |
 | `nonRuntime` | Explicit ordinary repository documentation, policy, non-shipped assets, and unit-test paths; no plugin harness launch |
 
+A change to `features/recipes.ts` can name any feature that has a recipe.
+
 A change to `plugins/pstack/.claude-plugin/plugin.json`, `.claude-plugin/marketplace.json`, or `plugins/pstack/.codex-plugin/plugin.json` is version-only when the merge base and the head hold the same regular file with the same mode, both sides parse as JSON objects, at least one version string changed (top-level `version`, or `plugins[].version` in the marketplace), and nothing else differs. A version-only change reaches only `hook:startup`: the two Claude files in Claude, the Codex manifest in Codex. `.agents/plugins/marketplace.json` has no version and always takes the shared expansion.
 
 Asset ownership is consumer-driven, not blanket shared ownership. Inspect the exact candidate's plugin manifests. At present, `plugins/pstack/assets/logo.png` is referenced only by `plugins/pstack/.codex-plugin/plugin.json`, so a logo-only change selects the installed Codex asset surface and does not invent a Claude exercise. New shipped assets must be added to `assets` and must have a real manifest consumer; missing, ambiguous, or unknown consumption fails closed.
diff --git a/.claude/skills/verify-open-pstack/features/recipes.ts b/.claude/skills/verify-open-pstack/features/recipes.ts
index 8a006e4b..f9ec4361 100644
--- a/.claude/skills/verify-open-pstack/features/recipes.ts
+++ b/.claude/skills/verify-open-pstack/features/recipes.ts
@@ -130,9 +130,19 @@ async function ciFixed(_record: SessionRecord, f: Fixture): Promise<Evidence> {
   return { assertions: ['fixed:sum.mjs'], files: [join(f.dir, 'sum.mjs')] };
 }
 
+const SUM_OPERANDS = String.raw`(?:a[ \t]*\+[ \t]*b|b[ \t]*\+[ \t]*a)`;
+const RECOGNIZED_SUM = new RegExp(String.raw`^export function sum\(a, b\) \{\n[ \t]*return[ \t]+(?:${SUM_OPERANDS}|\([ \t]*${SUM_OPERANDS}[ \t]*\))[ \t]*;?[ \t]*\n\}\n?$`);
+
+async function sumRepairRecognized(_record: SessionRecord, f: Fixture): Promise<Evidence> {
+  if (await readFile(join(f.dir, 'sum.test.mjs'), 'utf8') !== TASK['sum.test.mjs']) throw new Error('test-changed:sum.test.mjs');
+  if (!RECOGNIZED_SUM.test(await readFile(join(f.dir, 'sum.mjs'), 'utf8'))) throw new Error('repair-not-recognized:sum.mjs');
+  return { assertions: ['recognized-repair:sum.mjs', 'test-unchanged:sum.test.mjs'], files: [join(f.dir, 'sum.mjs'), join(f.dir, 'sum.test.mjs')] };
+}
+
 const overrides: Record<string, Case> = {
   'fix-ci': skillCase('fix-ci', 'There is no pull request or remote. The failing CI check is the local command `sh ci.sh` in $DIR. Fix it locally and do not push.', ciFixed),
   babysit: skillCase('babysit', 'The pull request is the local `main` branch of the repository at $DIR; there is no remote. Its one failing check is the local command `sh ci.sh`. Do exactly one babysit pass: fix the failing check locally, push nothing, change nothing remote, then stop instead of watching.', ciFixed),
+  'principle-never-block-on-the-human': skillCase('principle-never-block-on-the-human', 'The bug in $DIR/TASK.md is a reversible local change. Apply the skill: implement the smallest fix in sum.mjs and verify it with bun sum.test.mjs.', sumRepairRecognized),
   'make-pr-easy-to-review': skillCase('make-pr-easy-to-review', 'The pull request is the local branch `feature` against `main` in $DIR; there is no remote. Do not rewrite history or push; write reviewer guidance only.', async (_record, f) => {
     if ((await git(f, 'rev-parse', 'feature')).trim() !== (await readFile(`${f.dir}.head`, 'utf8')).trim()) throw new Error('history-rewritten:feature');
     return { assertions: ['history-unchanged'], files: [] };
diff --git a/.claude/skills/verify-open-pstack/features/skill-invocation.md b/.claude/skills/verify-open-pstack/features/skill-invocation.md
index 672e1b00..ecb6e541 100644
--- a/.claude/skills/verify-open-pstack/features/skill-invocation.md
+++ b/.claude/skills/verify-open-pstack/features/skill-invocation.md
@@ -22,6 +22,6 @@ A generic prompt about a skill is not native invocation evidence. A list of disc
 
 ## Headless
 
-`recipes.ts` gives every `skill-invocation:<name>` one default case: a disposable Git fixture holding a small task in `TASK.md`, a native invocation (`/pstack:<name>` in Claude, the Skill tool for principle leaves, `$pstack:<name>` in Codex), and an instruction to write the result to `result.md` in the fixture. It asserts that the native record shows the `pstack:<name>` skill load and that the session wrote a nonempty `result.md`. Skills whose normal use would push, merge, post, or write daily state override it: `fix-ci`, `babysit`, and `make-pr-easy-to-review` run against a local fixture with no remote and assert a local effect, and `automate-me` writes its draft into the fixture instead of the daily skills folder. `setup-pstack` uses the setup recipe. `project-skill` runs from the candidate checkout and asserts the skill load, the doctor command, and the canonical-path `doctor.json`.
+`recipes.ts` gives every `skill-invocation:<name>` one default case: a disposable Git fixture holding a small task in `TASK.md`, a native invocation (`/pstack:<name>` in Claude, the Skill tool for principle leaves, `$pstack:<name>` in Codex), and an instruction to write the result to `result.md` in the fixture. It asserts that the native record shows the `pstack:<name>` skill load and that the session wrote a nonempty `result.md`. Skills whose case needs a concrete local effect or a disposable fixture override it: `fix-ci`, `babysit`, and `make-pr-easy-to-review` run against a local fixture with no remote and assert a local effect, `principle-never-block-on-the-human`'s repair must leave `sum.mjs` as a recognized form of the add function (`return a + b` or `return b + a`, optionally parenthesized, with or without a semicolon) and the fixture's `sum.test.mjs` unchanged, and the verifier executes neither file, so a report that only waits for approval, or a failed repair, fails, and `automate-me` writes its draft into the fixture instead of the daily skills folder. `setup-pstack` uses the setup recipe. `project-skill` runs from the candidate checkout and asserts the skill load, the doctor command, and the canonical-path `doctor.json`.
 
 `reflect` has two cases in each harness that exercise step 1 only, against run-owned synthetic transcripts with metadata before the opening user message. The prompts name the opening prompt and, for Codex, the known chat ID and a fixture-only `CODEX_HOME`, or, for Claude, the fixture's per-project directory. They do not name the resolver or the transcript file, so the installed active-transcript mapping must lead the session there. In `locate-transcript` the transcript's opener matches. The case asserts the opening-message metadata and that no digest was written. In `digest-fallback` the opener differs, and the case asserts a nonblank digest of at most 2,000 words. Each run uses a per-run nonce that no prompt contains. For Codex, it is in the fixture rollout's file name. A completed command must name the installed resolver's launcher or script by absolute path, and its harness-captured output must parse to exactly the resolver JSON for this run, key order aside. Failed or pending commands and output from another fixture or run do not count, and a report file the model writes is never the Codex execution evidence. For Claude, the nonce is the opening user record's `uuid`, which only the transcript holds. In both cases the report must equal the expected JSON exactly, including that `uuid`: under `opening_user_message` when the opener matches, and beside the fallback status when it does not. A report without the `uuid`, or with another run's, does not count. These cases do not exercise reviewer fan-out, synthesis, or skill edits.
diff --git a/.claude/skills/verify-open-pstack/scripts/core.test.ts b/.claude/skills/verify-open-pstack/scripts/core.test.ts
index 16417a7d..455fd0d1 100644
--- a/.claude/skills/verify-open-pstack/scripts/core.test.ts
+++ b/.claude/skills/verify-open-pstack/scripts/core.test.ts
@@ -2,6 +2,7 @@ import { describe, expect, test } from 'bun:test';
 import { execFileSync } from 'node:child_process';
 import { resolve } from 'node:path';
 import registryData from '../features/registry.json';
+import { recipe } from '../features/recipes.ts';
 import { classify, completeEvidence, matches, newReceipt, requiredFeatures, requiredHarnesses, validateRegistry } from './core.ts';
 import { HARNESSES, type Receipt } from './types.ts';
 import codexManifest from '../../../../plugins/pstack/.codex-plugin/plugin.json';
@@ -181,6 +182,35 @@ describe('registry and ownership', () => {
     evidence(r);
     expect(() => completeEvidence(r)).not.toThrow();
   });
+  test('the shared recipe implementation reaches every implemented recipe and preserves project proof', () => {
+    const path = '.claude/skills/verify-open-pstack/features/recipes.ts';
+    const expected = [...both('catalog', 'setup', 'runner', 'shipped-tools', 'hook:startup', 'project-skill',
+      ...registry.skills.map(skill => `skill-invocation:${skill}`)), 'claude:agent-preload:poteto-agent'].sort();
+    for (const file of [{ filename: path }, { filename: 'docs/moved.md', previous_filename: path }]) {
+      const s = classify([file], registry);
+      expect(s.features).toEqual(expected);
+      expect(s.skills).toEqual([...registry.skills].sort());
+      expect(s.noRuntime).toBe(false);
+      for (const harness of HARNESSES) {
+        for (const feature of s.features.filter(f => f.startsWith(`${harness}:`))) {
+          expect(recipe(feature.slice(harness.length + 1), harness).length).toBeGreaterThan(0);
+        }
+      }
+    }
+  });
+  test('nearby verifier documentation retains only project proof', () => {
+    for (const filename of ['.claude/skills/verify-open-pstack/features/README.md',
+      '.claude/skills/verify-open-pstack/features/skill-invocation.md']) {
+      expect(classify([{ filename }], registry).features).toEqual(both('project-skill'));
+    }
+  });
+  test('shared recipe expansion survives overlapping catalog ownership without broadening ordinary catalog paths', () => {
+    const path = '.claude/skills/verify-open-pstack/features/recipes.ts';
+    const overlapping = { ...registry, catalog: [...registry.catalog, path], shared: [...registry.shared, path] };
+    expect(classify([{ filename: path }], overlapping)).toEqual(classify([{ filename: path }], registry));
+    const catalog = registry.catalog[0]!;
+    expect(classify([{ filename: catalog }], overlapping)).toEqual(classify([{ filename: catalog }], registry));
+  });
   test('ordinary repository documentation selects no harnesses', () => {
     const s = classify([{ filename: 'README.md' }, { filename: 'docs/guide.md' }], registry);
     expect(s.noRuntime).toBe(true);
diff --git a/.claude/skills/verify-open-pstack/scripts/core.ts b/.claude/skills/verify-open-pstack/scripts/core.ts
index 4ad84523..6cf3c99d 100644
--- a/.claude/skills/verify-open-pstack/scripts/core.ts
+++ b/.claude/skills/verify-open-pstack/scripts/core.ts
@@ -34,9 +34,11 @@ export function classify(files: ChangedFile[], registry: Registry): Selection {
       if (path !== 'plugins/pstack/assets/logo.png') throw new Error(`Unmapped asset consumer: ${path}`);
       features.add('codex:assets:codex'); covered = true;
     }
+    const sharedRecipe = path === '.claude/skills/verify-open-pstack/features/recipes.ts';
+    if (sharedRecipe) both('catalog');
     const catalog = registry.catalog.some(p => matches(path, p));
     if (catalog) { both('catalog', 'setup', 'runner'); covered = true; }
-    if (!catalog && registry.shared.some(p => matches(path, p))) {
+    if (sharedRecipe || (!catalog && registry.shared.some(p => matches(path, p)))) {
       registry.skills.forEach(s => skills.add(s));
       both('setup', 'runner', 'shipped-tools', 'hook:startup');
       features.add('claude:agent-preload:poteto-agent');
diff --git a/.claude/skills/verify-open-pstack/scripts/skill-invocation.test.ts b/.claude/skills/verify-open-pstack/scripts/skill-invocation.test.ts
new file mode 100644
index 00000000..8a187ffb
--- /dev/null
+++ b/.claude/skills/verify-open-pstack/scripts/skill-invocation.test.ts
@@ -0,0 +1,66 @@
+import { afterEach, describe, expect, test } from 'bun:test';
+import { mkdtemp, realpath, rm, writeFile } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { recipe, type Case, type Fixture } from '../features/recipes.ts';
+import { command } from './io.ts';
+import type { Harness, SessionRecord } from './types.ts';
+
+const roots: string[] = [];
+afterEach(async () => { for (const root of roots.splice(0)) await rm(root, { recursive: true, force: true }); });
+const skill = 'principle-never-block-on-the-human';
+
+async function waitingSession(harness: Harness): Promise<{ f: Fixture; c: Case; record: SessionRecord }> {
+  const dir = await realpath(await mkdtemp(join(tmpdir(), 'pstack-never-block-'))); roots.push(dir);
+  const f = { harness, dir, workspace: dir, location: dir, configHome: dir, run: command };
+  const c = recipe(`skill-invocation:${skill}`, harness)[0]!;
+  await c.prepare!(f);
+  const record = { harness, exitCode: 0, started: Date.now() - 1000, skills: [`pstack:${skill}`], commands: [], tools: [], context: [] };
+  await writeFile(join(dir, 'result.md'), 'Waiting for you to approve inspection. I did not inspect anything.');
+  return { f, c, record };
+}
+
+const harnesses: Harness[] = ['claude', 'codex'];
+const sumWith = (body: string) => `export function sum(a, b) {\n${body}\n}\n`;
+
+const recognized = [
+  '  return a + b;',
+  '  return a + b',
+  '  return b + a;',
+  '  return (a + b);',
+  '  return ( b+a ) ;',
+  '\treturn a+b;',
+];
+
+const unrecognized = [
+  '  return a - b;',
+  '  return a + b - 1;',
+  '  return a +;',
+  '  return (a + b;',
+  '  return a + b; // fixed',
+  '  return a + b; x();',
+  '  return\n  a + b;',
+  '  return a + b;\n  return 0;',
+];
+
+describe.each(harnesses)('%s never-block case', harness => {
+  test.each(recognized)('accepts %j and the fixture test passes on it', async body => {
+    const { f, c, record } = await waitingSession(harness);
+    await writeFile(join(f.dir, 'sum.mjs'), sumWith(body));
+    expect((await c.assert(record, f)).assertions).toEqual(expect.arrayContaining(['recognized-repair:sum.mjs', 'test-unchanged:sum.test.mjs']));
+    await command(['bun', 'sum.test.mjs'], { cwd: f.dir });
+  });
+
+  test.each(unrecognized)('rejects %j', async body => {
+    const { f, c, record } = await waitingSession(harness);
+    await writeFile(join(f.dir, 'sum.mjs'), sumWith(body));
+    await expect(c.assert(record, f)).rejects.toThrow('repair-not-recognized:sum.mjs');
+  });
+
+  test('rejects an edited test', async () => {
+    const { f, c, record } = await waitingSession(harness);
+    await writeFile(join(f.dir, 'sum.mjs'), sumWith('  return a + b;'));
+    await writeFile(join(f.dir, 'sum.test.mjs'), "import { sum } from './sum.mjs';\nsum(2, 3);\n");
+    await expect(c.assert(record, f)).rejects.toThrow('test-changed:sum.test.mjs');
+  });
+});
diff --git a/.claude/skills/verify-open-pstack/scripts/verify.test.ts b/.claude/skills/verify-open-pstack/scripts/verify.test.ts
index ea2c7c65..ecf07c36 100644
--- a/.claude/skills/verify-open-pstack/scripts/verify.test.ts
+++ b/.claude/skills/verify-open-pstack/scripts/verify.test.ts
@@ -115,6 +115,28 @@ describe('exact-head evidence publication', () => {
     expect((await verify(f.options)).status).toBe('success');
     expect(f.calls).toContain('prepare');
   });
+  test('a shared recipe change runs only the named recipe and project proof from the candidate publisher', async () => {
+    const selected = 'codex:skill-invocation:principle-never-block-on-the-human';
+    for (const revision of [REVISION, SHA]) {
+      const f = fixture(true);
+      f.options.publisherRevision = revision;
+      f.options.features = [selected];
+      f.options.github.files = async () => [{ filename: '.claude/skills/verify-open-pstack/features/recipes.ts' }];
+      if (revision !== SHA) {
+        await expect(verify(f.options)).rejects.toThrow('rerun from that checkout');
+        expect(f.calls.some(call => ['preflight', 'prepare', 'exercise', 'comment'].includes(call) || call.startsWith('status:'))).toBe(false);
+      } else {
+        const receipt = await verify(f.options);
+        expect(receipt.status).toBe('success');
+        expect(receipt.runFeatures).toEqual([selected, 'claude:project-skill', 'codex:project-skill']);
+        expect(receipt.selection.features.length).toBeGreaterThan(receipt.runFeatures.length);
+        expect(receipt.sessions).toBe(3);
+        expect(receipt.observations.map(record => `${record.harness}/${record.feature}`).sort()).toEqual([
+          'claude/project-skill', 'codex/project-skill', 'codex/skill-invocation:principle-never-block-on-the-human',
+        ]);
+      }
+    }
+  });
 
   test('successful verification restores setup and removes Codex run state before any publication', async () => {
     const f = fixture(true); f.options.driver.cleanup = async () => { f.calls.push('cleanup'); };