test(qa-callers): admit review-army's specialist diff at the fixture merge base (screen 40737741454 ship-exploratory-unavailable)

The review plan dispatches the state-machines specialist, and review-army tells the
parent to write the merge-base sha into its diff command. Both screen trials failed
on that child's git diff <merge-base sha>. Also: cite the deadline loop beside the
identity_* cookie-auth cases (GStack Minder accepted the 400 ms narrowing).

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -6,13 +6,13 @@
 
 ### Fixed
 - **Shared-code reuse no longer lets a review rewrite the index flags it checks.** In train gate 40619718717, the reviewer ran `git update-index --really-refresh` while gathering evidence. That cleared the assume-unchanged flag the checker reads, so the trial's prerequisites went stale. Step 1 of the /review and /ship shared-code reuse section now says evidence gathering is read-only and names that command. Nearby wording was tightened so the section keeps its exact size.
-- **The /ship exploratory-QA cases follow Step 9's review plan again.** Since #3527, Step 9 runs `gstack-review-plan --base main`. The fixture refused that command (paid screen 40707142223, both ship-exploratory-plan-checks trials) and never said that the plan's adversarial-native and outside-voice lines belong to Step 11, which is outside the fixture's Steps 8–9 excerpt. In gate 40664336141, ship-exploratory-late-input reported pass while listing that Step 11 pass as remaining work.
+- **The /ship exploratory-QA cases follow Step 9's review plan again.** Since #3527, Step 9 runs `gstack-review-plan --base main`. The fixture refused that command (paid screen 40707142223, both ship-exploratory-plan-checks trials) and never said that the plan's adversarial-native and outside-voice lines belong to Step 11, which is outside the fixture's Steps 8–9 excerpt. In gate 40664336141, ship-exploratory-late-input reported pass while listing that Step 11 pass as remaining work. Once the plan ran, it dispatched the state-machines specialist, and review-army tells the parent to write the merge-base sha into that specialist's diff command. The fixture refused `git diff <merge-base sha>`, which failed both ship-exploratory-unavailable trials in this PR's screen 40737741454.
 - **The real-browser cookie-auth checks no longer time out under load.** The positive case and the rejection cases that return early now use the product's default 15 s limit instead of a 400 ms test-only value. That value timed out twice on Windows and once on a Ubicloud VM.
 
 ### Gate integrity
-- `test/helpers/qa-callers-fixture.ts`: the caller command interface now admits the `gstack-review-plan` forms ship Step 9 names (`--base main` with its `--pass`, `--last` and finding flags, or `--fix-check-prompt` with literal file arguments), only at the fixture's installed helper path. Pipes, other arguments, other binaries and calls without the fixture's runtime are refused, and `test/qa-caller-review-plan.test.ts` checks these as negative controls. The ship prompt names the Step 11 boundary. No threshold, trial count, case kind or timeout changed.
+- `test/helpers/qa-callers-fixture.ts`: the caller command interface now admits the `gstack-review-plan` forms ship Step 9 names (`--base main` with its `--pass`, `--last` and finding flags, or `--fix-check-prompt` with literal file arguments), only at the fixture's installed helper path. Pipes, other arguments, other binaries and calls without the fixture's runtime are refused, and `test/qa-caller-review-plan.test.ts` checks these as negative controls. The ship prompt names the Step 11 boundary. The interface also admits the fixture's own merge base (at least 7 hex characters) as a literal diff base, bare or in review-army's `DIFF_BASE=<sha> && git diff "$DIFF_BASE"` specialist form, and the prompt declares it. Any other sha, a shorter prefix, other Git options and composition are still refused. No threshold, trial count, case kind or timeout changed.
 - `browse/test/cookie-auth-verification.test.ts`: GStack Minder approved dropping the shared `timeoutMs: 400`, which came from a84b0b5b6 (#2964) as a fixture value no product path uses (`--verify-auth` callers run under `MAX_TIMEOUT_MS` 15000). The identity mismatch, missing and ambiguous cases keep 400 ms because they resolve only at the deadline, and the 15 s default would exceed bun's 5 s test timeout. The explicit 100 ms, 30 ms, 60 s-cap and invalid-timeout tests are unchanged.
-- New free tests: `test/qa-caller-review-plan.test.ts` (replays both 40707142223 captures and runs the real plan for all four ship cases) and `test/shared-libs-index-flags-readonly.test.ts` (replays the captured refresh against the assume-unchanged fixture, with a read-only control).
+- New free tests: `test/qa-caller-review-plan.test.ts` (replays both 40707142223 captures and both 40737741454 ship-exploratory-unavailable captures, and runs the real plan for all four ship cases) and `test/shared-libs-index-flags-readonly.test.ts` (replays the captured refresh against the assume-unchanged fixture, with a read-only control).
 - `scripts/lib/windows-curation.ts`: `test/shared-libs-index-flags-readonly.test.ts` is curated off the Windows subset. Its fixture starts the review through `bin/gstack-review-log`, a bash script, which windows-latest cannot launch (Windows Free Tests run 40727825859, shard 5).
 
 ## [1.91.295.0] - 2026-10-28

browse/test/cookie-auth-verification.test.ts

@@ -507,6 +507,7 @@ describe('cookie authentication and storage with isolated Chromium profiles', ()
     test(`rejects ${path} with a safe ${reason} result`, async () => {
       await page.goto(`${origin}${path === '/login-hop' ? '/identity' : path}`);
       if (path === '/login-hop') await page.evaluate(() => history.replaceState({}, '', '/login-hop'));
+      // identity_mismatch/missing/ambiguous keep the 400 ms options (GStack Minder, 2026-10-28): they resolve only when the deadline fires (browse/src/cookie-auth-verification.ts:105-120), so the 15 s default would exceed bun's 5 s test timeout.
       const result = await verifyCookieAuthentication(page, reason.startsWith('identity_') ? options : browserOptions, origin);
       expect(result.verified).toBe(false);
       expect(result.reason).toBe(reason);

test/fixtures/qa-caller-merge-base-diff-40737741454.json

@@ -0,0 +1,101 @@
+{
+  "source": "Paid screen 40737741454 (#3553 head 4cd0777) ship-exploratory-unavailable: paid-slice-11-a1 and paid-rerun-1-a1 native-events.json, every Bash command in order (parent and child). In both trials the review plan dispatched the state-machines specialist, and the parent told it to run git diff with the literal merge-base sha.",
+  "runs": {
+    "40737741454-slice-11": {
+      "root": "/home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs",
+      "mergeBase": "8c9a9c5",
+      "commands": [
+        {
+          "parent": false,
+          "command": "date -u +%Y-%m-%dT%H:%M:%SZ"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/host/runtime/bin/gstack-qa-deadline start /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/product/reports/deadline.json 300 2026-10-28T18:00:28.179Z"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/host/runtime/bin/gstack-qa-evidence capture /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/product/reports 001 --public --deadline /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/product/reports/deadline.json -- bun scripts/probe.ts 4"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/host/runtime/bin/gstack-qa-deadline status /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/product/reports/deadline.json"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/host/runtime/bin/gstack-qa-evidence capture /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/product/reports 002 --public --deadline /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/product/reports/deadline.json --after 001 --hypothesis 'Riskiest changed edge: out-of-range 10 must exit 2 with the declared stderr; also confirms whether the missing native-engine prerequisite blocks every CLI path' -- bun scripts/probe.ts 10"
+        },
+        {
+          "parent": false,
+          "command": "bun run test"
+        },
+        {
+          "parent": false,
+          "command": "/home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/host/runtime/bin/gstack-review-plan --base main"
+        },
+        {
+          "parent": true,
+          "command": "git diff 8c9a9c5"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/host/runtime/bin/gstack-qa-evidence materialize /home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/product/reports annotations.json"
+        },
+        {
+          "parent": false,
+          "command": "git status --short"
+        },
+        {
+          "parent": false,
+          "command": "/home/runner/.cache/gstack-paid-shard-hEauF9/tmp/qc-qBCQGs/host/runtime/bin/gstack-review-log '{\"skill\":\"review\",\"timestamp\":\"'\"$(date -u +%Y-%m-%dT%H:%M:%SZ)\"'\",\"status\":\"issues_found\",\"issues_found\":0,\"critical\":0,\"informational\":0,\"quality_score\":10,\"specialists\":{\"state-machines\":{\"dispatched\":true,\"findings\":0,\"critical\":0,\"informational\":0},\"red-team\":{\"dispatched\":false,\"reason\":\"scope\"}},\"findings\":[],\"commit\":\"'\"$(git rev-parse --short HEAD)\"'\",\"via\":\"ship\",\"completed\":false,\"converged\":false,\"cycles\":0,\"pass\":1,\"review_scope\":\"frozen\",\"range_base\":null}' --finish bbf15eec-7962-4aee-bcfd-88233b0375fe"
+        }
+      ]
+    },
+    "40737741454-rerun-1": {
+      "root": "/home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK",
+      "mergeBase": "0f7b81c",
+      "commands": [
+        {
+          "parent": false,
+          "command": "date -u +%Y-%m-%dT%H:%M:%SZ"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/host/runtime/bin/gstack-qa-deadline start /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/product/reports/deadline.json 300 2026-10-28T18:18:29.666Z"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/host/runtime/bin/gstack-qa-evidence capture /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/product/reports 001 --public --deadline /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/product/reports/deadline.json -- bun scripts/probe.ts 3"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/host/runtime/bin/gstack-qa-evidence capture /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/product/reports 002 --public --deadline /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/product/reports/deadline.json --after 001 --hypothesis 'Success path blocked by missing vendor/native-engine.ts; check whether the riskiest changed edge (out-of-range 10) is equally blocked before reaching scale().' -- bun scripts/probe.ts 10"
+        },
+        {
+          "parent": false,
+          "command": "bun run test"
+        },
+        {
+          "parent": false,
+          "command": "/home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/host/runtime/bin/gstack-review-plan --base main"
+        },
+        {
+          "parent": true,
+          "command": "git diff 0f7b81c"
+        },
+        {
+          "parent": false,
+          "command": "bun /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/host/runtime/bin/gstack-qa-evidence materialize /home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/product/reports annotations.json"
+        },
+        {
+          "parent": false,
+          "command": "git status --short"
+        },
+        {
+          "parent": false,
+          "command": "/home/runner/.cache/gstack-paid-shard-2u70Ma/tmp/qc-lV9GKK/host/runtime/bin/gstack-review-log '{\"skill\":\"review\",\"timestamp\":\"'\"$(date -u +%Y-%m-%dT%H:%M:%SZ)\"'\",\"status\":\"issues_found\",\"issues_found\":0,\"critical\":0,\"informational\":0,\"quality_score\":10,\"specialists\":{\"state-machines\":{\"dispatched\":true,\"findings\":0,\"critical\":0,\"informational\":0},\"testing\":{\"dispatched\":false,\"reason\":\"scope\"},\"maintainability\":{\"dispatched\":false,\"reason\":\"scope\"},\"red-team\":{\"dispatched\":false,\"reason\":\"scope\"}},\"findings\":[],\"commit\":\"'\"$(git rev-parse --short HEAD)\"'\",\"via\":\"ship\",\"completed\":false,\"converged\":false,\"cycles\":0,\"pass\":1,\"review_scope\":\"frozen\",\"range_base\":null}' --finish 4b1c9f3b-d67b-4919-8237-21634b5b4c0b"
+        }
+      ]
+    }
+  }
+}

test/helpers/free-fixtures-data.ts

@@ -178,6 +178,7 @@ export const FREE_FIXTURES: Readonly<Record<string, readonly string[]>> = {
   'test/fixtures/plan-floor-edit-wrap-37176835584.json': ['test/plan-floor-edit-wrap.test.ts'],
   'test/fixtures/plan-format-kind-notes.json': ['test/plan-format-kind-note.test.ts'],
   'test/fixtures/qa-caller-handoff-order-public.json': ['test/qa-exploratory-callers.test.ts'],
+  'test/fixtures/qa-caller-merge-base-diff-40737741454.json': ['test/qa-caller-review-plan.test.ts'],
   'test/fixtures/qa-caller-read-probe-mtb1007a.json': ['test/qa-exploratory-callers.test.ts'],
   'test/fixtures/qa-caller-review-plan-40707142223.json': ['test/qa-caller-review-plan.test.ts'],
   'test/fixtures/qa-caller-section-skip-ship-small-cli.json': ['test/qa-exploratory-callers.test.ts'],

test/helpers/qa-callers-fixture.ts

@@ -140,6 +140,14 @@ const literalCallerListing = new RegExp(`^ls(?: -[la]+)?(?: --)?(?: ${literalCal
 const callerDiffMode = '(--stat|--numstat|--name-only|--name-status)';
 const literalCallerDiff = new RegExp(`^git diff(?: ${callerDiffMode})?(?: (origin/main|"\\$DIFF_BASE"))?(?: ${callerDiffMode})?(?: --(?: ${literalCallerArgument})+)?$`);
 const callerDiffPreface = 'DIFF_BASE=$(git merge-base origin/main HEAD) && ';
+const literalMergeBaseDiff = new RegExp(`^(?:DIFF_BASE=([0-9a-f]{7,40}) && )?git diff(?: ${callerDiffMode})? ([0-9a-f]{7,40}|"\\$DIFF_BASE")(?: ${callerDiffMode})?(?: --(?: ${literalCallerArgument})+)?$`);
+
+function mergeBaseDiffAllowed(text: string, context?: CallerDeadlineContext): boolean {
+  const diff = literalMergeBaseDiff.exec(text);
+  if (!diff || !context || (diff[2] && diff[4]) || !!diff[1] !== (diff[3] === '"$DIFF_BASE"')) return false;
+  const base = spawnSync('git', ['merge-base', 'origin/main', 'HEAD'], { cwd: context.fixtureRoot, encoding: 'utf8', timeout: 5000 });
+  return base.status === 0 && base.stdout.trim().startsWith(diff[1] ?? diff[3]);
+}
 
 function literalCallerDiffAllowed(text: string): boolean {
   const recomputedBase = text.startsWith(callerDiffPreface);
@@ -237,6 +245,7 @@ export function qaCallerCommandAllowed(command: string, workflowCommands: string
   if (workflowCommands.includes(text)) return true;
   if (literalCallerCLI.test(text)) return true;
   if (literalCallerDiffAllowed(text)) return true;
+  if (mergeBaseDiffAllowed(text, deadline)) return true;
   if (literalCallerListingAllowed(text)) return true;
   let normalizedRecord = text;
   const substitutedFields: string[] = [];
@@ -709,7 +718,7 @@ export function callerReviewRecordTemplate(fixture: Pick<QaCallerFixture, 'calle
 
 export function qaCallerSessionOptions(fixture: QaCallerFixture, runId: string): Parameters<typeof runSkillTest>[0] {
   return {
-    prompt: `Load gstack's /${fixture.caller} supplied parent phase from caller-${fixture.caller}.md and resume it on the selected working-tree diff against origin/main. This excerpt comes from ${fixture.runtime}/${fixture.caller}/SKILL.md; resolve installed-relative references there, not from the excerpt file or product directory. That path identifies the asset base, not another entrypoint: do not read or invoke the full parent SKILL.md or rerun its preamble. Earlier preamble/branch/base setup is complete; use the existing local origin/main ref without fetch. Earlier-phase asset locators are ${fixture.runtime}/review/checklist.md and ${fixture.runtime}/qa/templates/functional-report-template.md. Read those files directly when referenced; recursive Glob does not follow the installed asset symlinks. Cross-project learnings are configured off in this owned fixture. ${fixture.reviewStart ? `The actual review-start helper already captured REVIEW_START=${fixture.reviewStart} for this unchanged core pass; retain that token. ` : ''} This fixture evaluates only the supplied parent phase, not later publication stages. The fixture owner recorded these read-only observations when this phase began; they are current until an input changes, so use them instead of re-running those commands, and recheck freshness before completion outputs:\n${fixture.startObservations}\n Read README.md for the project contract and commands. Use diagnostic-client commands such as \`bun scripts/probe.ts <literal>\` for exploratory discoveries and their checkpoint evidence. A required \`bun run test\` is separate suite verification: report it as verification, never as a diagnostic observation or checkpoint anchor/target. Use the production evidence helper to publish each diagnostic checkpoint as \`reports/exploration-NNN.json\`, not inside a nested directory; do not transcribe its observed payload. ${fixture.caseId === 'ship-exploratory-plan-checks' ? 'The previously discovered plan is PLAN.md.' : 'No plan file was found.'} There is no remote service and no release publication is authorized. There is no interactive approver; do not invent answers or permission. Keep normal parent decision gates. Handoff freshness check: Read HANDOFF.md and reports/HANDOFF.md if present for any concurrent collaborator update, await those results, and compare evidence with current inputs; rerun any probe whose input changed. Run the check before each of these, and dispatch each only in a later message than the check's Read results: the evidence helper's materialize, which runs once per report root and freezes the verdict; every gstack-review-log completed:true record, adversarial-review included, since a record is a completion, not preliminary bookkeeping; and the completion report. A later handoff read cannot validate an earlier materialize or completion. If a probe's snapshot differs from an earlier probe's, read reports/HANDOFF.md first; it names any collaborator change.\n\nQA fixture bindings: the deadline guard, capture, checkpoint and materialize command forms are in the installed qa/sections/exploratory.md this phase requires you to Read; use those forms verbatim with these bindings substituted literally. DEADLINE_TOOL = ${fixture.runtime}/bin/gstack-qa-deadline. EVIDENCE_TOOL = ${fixture.runtime}/bin/gstack-qa-evidence. PROBE_DIR = ${fixture.cwd}/reports. DEADLINE_FILE = ${fixture.cwd}/reports/deadline.json. SECONDS must be positive and at most 300. EARLIER_UTC is the optional caller absolute deadline: use the section clock's Hard deadline UTC, never its Runner entry UTC, reserve-start time or a clock-read time. The only native COMMAND is the existing diagnostic client, bun scripts/probe.ts, with zero or one literal argument. Resolve these exact helper and state paths; do not use variables, another helper, another state file, nested wrappers, scripts, operators or substitutions. Its diagnostic receipts are declared public/synthetic, so --public is approved. Only an explicit plan check this phase requires may use --timeout-ms 10000 in place of the deadline; every other capture, including a rerun or revalidation of an earlier probe, uses the deadline. This does not reset or bypass the smoke deadline. Only the deadline helper may create or change reports/deadline.json and its .qa-deadline- temporary files; never use Write/Edit/MultiEdit on those paths. Record the full outer command in checkpoints and evidence; keep the unchanged child JSON as observed, separate from prefixed guard diagnostics. A completed expired guard-run is not a probe or a pass: retain its unused checkpoint, report not-run coverage and do not restart the deadline. Keep the 12-probe smoke limit. Required suites and explicit plan checks are outside the bounded smoke budget, not permission to reset it. Quote arguments literally. Sources stay inside reports. Decide to execute the next probe before publishing its checkpoint, then await successful publication and dispatch that exact probe. I
Line truncated
+    prompt: `Load gstack's /${fixture.caller} supplied parent phase from caller-${fixture.caller}.md and resume it on the selected working-tree diff against origin/main. This excerpt comes from ${fixture.runtime}/${fixture.caller}/SKILL.md; resolve installed-relative references there, not from the excerpt file or product directory. That path identifies the asset base, not another entrypoint: do not read or invoke the full parent SKILL.md or rerun its preamble. Earlier preamble/branch/base setup is complete; use the existing local origin/main ref without fetch. Earlier-phase asset locators are ${fixture.runtime}/review/checklist.md and ${fixture.runtime}/qa/templates/functional-report-template.md. Read those files directly when referenced; recursive Glob does not follow the installed asset symlinks. Cross-project learnings are configured off in this owned fixture. ${fixture.reviewStart ? `The actual review-start helper already captured REVIEW_START=${fixture.reviewStart} for this unchanged core pass; retain that token. ` : ''} This fixture evaluates only the supplied parent phase, not later publication stages. The fixture owner recorded these read-only observations when this phase began; they are current until an input changes, so use them instead of re-running those commands, and recheck freshness before completion outputs:\n${fixture.startObservations}\n Read README.md for the project contract and commands. Use diagnostic-client commands such as \`bun scripts/probe.ts <literal>\` for exploratory discoveries and their checkpoint evidence. A required \`bun run test\` is separate suite verification: report it as verification, never as a diagnostic observation or checkpoint anchor/target. Use the production evidence helper to publish each diagnostic checkpoint as \`reports/exploration-NNN.json\`, not inside a nested directory; do not transcribe its observed payload. ${fixture.caseId === 'ship-exploratory-plan-checks' ? 'The previously discovered plan is PLAN.md.' : 'No plan file was found.'} There is no remote service and no release publication is authorized. There is no interactive approver; do not invent answers or permission. Keep normal parent decision gates. Handoff freshness check: Read HANDOFF.md and reports/HANDOFF.md if present for any concurrent collaborator update, await those results, and compare evidence with current inputs; rerun any probe whose input changed. Run the check before each of these, and dispatch each only in a later message than the check's Read results: the evidence helper's materialize, which runs once per report root and freezes the verdict; every gstack-review-log completed:true record, adversarial-review included, since a record is a completion, not preliminary bookkeeping; and the completion report. A later handoff read cannot validate an earlier materialize or completion. If a probe's snapshot differs from an earlier probe's, read reports/HANDOFF.md first; it names any collaborator change.\n\nQA fixture bindings: the deadline guard, capture, checkpoint and materialize command forms are in the installed qa/sections/exploratory.md this phase requires you to Read; use those forms verbatim with these bindings substituted literally. DEADLINE_TOOL = ${fixture.runtime}/bin/gstack-qa-deadline. EVIDENCE_TOOL = ${fixture.runtime}/bin/gstack-qa-evidence. PROBE_DIR = ${fixture.cwd}/reports. DEADLINE_FILE = ${fixture.cwd}/reports/deadline.json. SECONDS must be positive and at most 300. EARLIER_UTC is the optional caller absolute deadline: use the section clock's Hard deadline UTC, never its Runner entry UTC, reserve-start time or a clock-read time. The only native COMMAND is the existing diagnostic client, bun scripts/probe.ts, with zero or one literal argument. Resolve these exact helper and state paths; do not use variables, another helper, another state file, nested wrappers, scripts, operators or substitutions. Its diagnostic receipts are declared public/synthetic, so --public is approved. Only an explicit plan check this phase requires may use --timeout-ms 10000 in place of the deadline; every other capture, including a rerun or revalidation of an earlier probe, uses the deadline. This does not reset or bypass the smoke deadline. Only the deadline helper may create or change reports/deadline.json and its .qa-deadline- temporary files; never use Write/Edit/MultiEdit on those paths. Record the full outer command in checkpoints and evidence; keep the unchanged child JSON as observed, separate from prefixed guard diagnostics. A completed expired guard-run is not a probe or a pass: retain its unused checkpoint, report not-run coverage and do not restart the deadline. Keep the 12-probe smoke limit. Required suites and explicit plan checks are outside the bounded smoke budget, not permission to reset it. Quote arguments literally. Sources stay inside reports. Decide to execute the next probe before publishing its checkpoint, then await successful publication and dispatch that exact probe. I
Line truncated
     appendSystemPrompt: `Caller execution scheduling (fixture contract):
 This session has at most 25 assistant turns, including required verification and final artifacts. The command boundary applies to each Bash call, not to the number of independent tool calls in an assistant turn.
 After required clock and approval prerequisites settle, issue independent source Reads and read-only discovery together as separate native tool calls once their paths and inputs are known. Read-only discovery is Read, Glob, Grep and the declared inventory, Git and review-read forms; a capture, a deadline guard start or run, or a diagnostic-client run is a probe, never discovery. For example, after the first clock read, one response can Read the caller excerpt, README.md, every product file and the referenced checklist and templates. Wait for their results before decisions that depend on them.

test/qa-caller-review-plan.test.ts

@@ -18,6 +18,7 @@ import {
 } from './helpers/qa-callers-fixture';
 
 const captured = JSON.parse(fs.readFileSync(path.join(import.meta.dir, 'fixtures/qa-caller-review-plan-40707142223.json'), 'utf8'));
+const specialistDiff = JSON.parse(fs.readFileSync(path.join(import.meta.dir, 'fixtures/qa-caller-merge-base-diff-40737741454.json'), 'utf8'));
 const SHIP_CASES: QaCallerCase[] = ['ship-exploratory-small-cli', 'ship-exploratory-unavailable', 'ship-exploratory-plan-checks', 'ship-exploratory-late-input'];
 const fixtures: QaCallerFixture[] = [];
 afterEach(async () => {
@@ -94,3 +95,43 @@ describe('ship Step 9 review plan through the qa-callers transport', () => {
     } finally { fs.rmSync(reportRoot, { recursive: true, force: true }); }
   });
 });
+
+/**
+ * Paid screen 40737741454 (ship-exploratory-unavailable, slice 11 and its rerun): the plan dispatched the
+ * state-machines specialist, review-army tells the parent to write the merge-base sha into the specialist's
+ * diff command, and the only refused call in both trials was that child's `git diff <merge-base sha>`.
+ */
+describe('review-army specialist diff at the literal merge base', () => {
+  const mergeBase = (fixture: QaCallerFixture) => spawnSync('git', ['merge-base', 'origin/main', 'HEAD'], { cwd: fixture.cwd, encoding: 'utf8', timeout: 5000 }).stdout.trim();
+
+  for (const [run, trial] of Object.entries(specialistDiff.runs) as [string, { root: string; mergeBase: string; commands: { command: string }[] }][]) {
+    test(`captured ${run}: every Bash call, the specialist child's included, is inside the declared interface`, () => {
+      const fixture = fixtureFor('ship-exploratory-unavailable', true);
+      const base = mergeBase(fixture).slice(0, trial.mergeBase.length);
+      const commands = trial.commands.map(({ command }) => command.replaceAll(trial.root, fixture.root).replaceAll(trial.mergeBase, base));
+      expect(commands).toContain(`git diff ${base}`);
+      expect(commands.filter(command => !qaCallerCommandAllowed(command, fixture.workflowCommands, context(fixture)))).toEqual([]);
+    });
+  }
+
+  test('only the fixture merge base is admitted, bare or in the specialist DIFF_BASE form, and the prompt declares it', () => {
+    const fixture = fixtureFor('ship-exploratory-unavailable');
+    const base = mergeBase(fixture);
+    const allowed = (command: string) => qaCallerCommandAllowed(command, fixture.workflowCommands, context(fixture));
+    for (const command of [`git diff ${base}`, `git diff ${base.slice(0, 7)}`, `git diff --stat ${base.slice(0, 12)}`, `git diff ${base} -- scale.ts`,
+      `DIFF_BASE=${base} && git diff "$DIFF_BASE"`, `DIFF_BASE=${base.slice(0, 9)} && git diff --name-status "$DIFF_BASE"`]) {
+      expect(allowed(command), command).toBe(true);
+    }
+    const other = base.replace(/^./, base[0] === '0' ? '1' : '0');
+    for (const command of [`git diff ${other}`, `git diff ${base.slice(0, 6)}`, `git diff ${base} --output=reports/x`, `git diff --stat ${base} --numstat`,
+      `DIFF_BASE=${other} && git diff "$DIFF_BASE"`, `DIFF_BASE=${base} && git diff ${base}`, `DIFF_BASE=${base}; git diff "$DIFF_BASE"`,
+      `git diff "$DIFF_BASE"`, `DIFF_BASE=${base} && git diff "$DIFF_BASE" && git status --short`, `git diff ${base.toUpperCase()}`]) {
+      expect(allowed(command), command).toBe(false);
+    }
+    expect(qaCallerCommandAllowed(`git diff ${base}`, fixture.workflowCommands)).toBe(false);
+    for (const caseId of ['ship-exploratory-unavailable', 'review-exploratory-small-cli'] as QaCallerCase[]) {
+      expect(qaCallerSessionOptions(fixtureFor(caseId), 'free-review-plan').prompt).toContain(
+        'The merge base itself, the sha git merge-base origin/main HEAD prints (at least 7 characters), may replace origin/main as a literal diff base');
+    }
+  });
+});