diff --git a/.github/scripts/check-test-growth.mjs b/.github/scripts/check-test-growth.mjs
new file mode 100644
index 00000000000..b79fb8cd215
--- /dev/null
+++ b/.github/scripts/check-test-growth.mjs
@@ -0,0 +1,281 @@
+#!/usr/bin/env node
+/**
+ * Report how much test code a pull request adds, and flag large additions.
+ *
+ * Nothing else counts test lines: the size rules in AGENTS.md and the triage
+ * skill count production lines only. In September 2026, PRs added 1.84 test
+ * lines per production line in core, cli and web-shell, and the 8% of PRs
+ * adding 2,000 or more net test lines carried half of that growth (#13007
+ * removed 178,000 Core test lines, a few weeks of it). This step writes the
+ * numbers to the job summary on every PR and, at FLAG_THRESHOLD net test
+ * lines, emits a warning annotation so authors and reviewers see them. It
+ * reports only: nothing blocks on it.
+ *
+ * The diff is taken from the true merge base, which the compare API reports:
+ * the PR's base.sha is the base tip, and diffing against it would count the
+ * base's newer changes, reversed, on any branch that is behind. The lane's
+ * checkout is shallow, so the merge base is fetched at depth 1.
+ *
+ * Advisory only: every error is a warning and the step exits 0.
+ */
+import { execFile } from 'node:child_process';
+import { appendFileSync } from 'node:fs';
+import { pathToFileURL } from 'node:url';
+import { promisify } from 'node:util';
+
+const execFileAsync = promisify(execFile);
+
+export const FLAG_THRESHOLD = 2000;
+
+export const PACKAGES = ['core', 'cli', 'web-shell'];
+
+// Test code: test and spec files, test helpers, fixtures, mocks, snapshots.
+const TEST_PATTERNS = [
+  /\.(test|spec)\.[^/]+$/,
+  /\.test-helper\.[^/]+$/,
+  /\.fixtures\.json$/,
+  /\.snap$/,
+  /(^|\/)(test-setup|testUtils)\.ts$/,
+  /(^|\/)test-utils\.[^/]+$/,
+  /(^|\/)(__tests__|__mocks__|__fixtures__|__snapshots__|__e2e__|fixtures|test-utils|testUtils)\//,
+  /^packages\/web-shell\/client\/(e2e|test)\//,
+];
+const GENERATED = /(\.schema\.(ts|json)|\.generated\.ts)$|(^|\/)generated\//;
+const SOURCE = /\.(ts|tsx|mts|cts|js|jsx|mjs|cjs)$/;
+
+/** The package a path belongs to, or null outside the three packages. */
+export function packageOf(path) {
+  const match = /^packages\/([^/]+)\//.exec(path);
+  return match && PACKAGES.includes(match[1]) ? match[1] : null;
+}
+
+/** 'test', 'production' or 'other' (data, docs, styles, generated code). */
+export function classify(path) {
+  if (TEST_PATTERNS.some((pattern) => pattern.test(path))) return 'test';
+  if (GENERATED.test(path) || !SOURCE.test(path)) return 'other';
+  return 'production';
+}
+
+/** Parses `git diff --numstat`, skipping binary files ("-\t-\tpath"). */
+export function parseNumstat(text) {
+  const entries = [];
+  for (const line of text.split('\n')) {
+    const match = /^(\d+)\t(\d+)\t(.+)$/.exec(line);
+    if (match) {
+      entries.push({ added: +match[1], deleted: +match[2], path: match[3] });
+    }
+  }
+  return entries;
+}
+
+/** Added and deleted test and production lines per package, plus a total. */
+export function tally(entries) {
+  const zero = () => ({
+    test: { added: 0, deleted: 0 },
+    production: { added: 0, deleted: 0 },
+  });
+  const byPackage = Object.fromEntries(PACKAGES.map((name) => [name, zero()]));
+  const total = zero();
+  for (const { added, deleted, path } of entries) {
+    const name = packageOf(path);
+    const kind = classify(path);
+    if (!name || kind === 'other') continue;
+    for (const bucket of [byPackage[name][kind], total[kind]]) {
+      bucket.added += added;
+      bucket.deleted += deleted;
+    }
+  }
+  return { byPackage, total };
+}
+
+const net = ({ added, deleted }) => added - deleted;
+const fmt = (n) => Math.abs(n).toLocaleString('en-US');
+const signed = (n) => (n > 0 ? '+' : n < 0 ? '−' : '') + fmt(n);
+const cell = (counts) =>
+  `+${fmt(counts.added)} / −${fmt(counts.deleted)} (net ${signed(net(counts))})`;
+
+export function isFlagged({ total }) {
+  return net(total.test) >= FLAG_THRESHOLD;
+}
+
+export function renderSummary(tallied) {
+  const rows = PACKAGES.map(
+    (name) =>
+      `| ${name} | ${cell(tallied.byPackage[name].test)} | ` +
+      `${cell(tallied.byPackage[name].production)} |`,
+  );
+  const lines = [
+    '### Test growth',
+    '',
+    '| Package | Test lines | Production lines |',
+    '| --- | ---: | ---: |',
+    ...rows,
+    `| **Total** | ${cell(tallied.total.test)} | ${cell(tallied.total.production)} |`,
+    '',
+  ];
+  if (isFlagged(tallied)) {
+    lines.push(
+      `This PR adds ${fmt(net(tallied.total.test))} net test lines, at or ` +
+        `above the ${fmt(FLAG_THRESHOLD)}-line flag. Consider whether shared ` +
+        'fixtures, parameterized tables or whole-result expectations would ' +
+        'cover the same behavior in less code.',
+      '',
+    );
+  }
+  return lines.join('\n');
+}
+
+export function renderAnnotation(tallied) {
+  if (!isFlagged(tallied)) return null;
+  return (
+    `::warning title=Test growth::This PR adds ` +
+    `${fmt(net(tallied.total.test))} net test lines in core, cli and ` +
+    `web-shell (flag at ${fmt(FLAG_THRESHOLD)}). ` +
+    'Consider shared fixtures or parameterized tables; see the job summary.'
+  );
+}
+
+/**
+ * curl, not fetch: it honours HTTPS_PROXY on the ECS runners' egress, which
+ * node's global fetch does not (see check-lint-gate-freshness.mjs).
+ */
+export async function curlJson(path, token, run = execFileAsync) {
+  try {
+    const { stdout } = await run(
+      'curl',
+      [
+        '-sS',
+        '-fL',
+        '--max-time',
+        '30',
+        '-H',
+        `Authorization: Bearer ${token}`,
+        '-H',
+        'Accept: application/vnd.github+json',
+        '-H',
+        'X-GitHub-Api-Version: 2022-11-28',
+        `https://api.github.com${path}`,
+      ],
+      { maxBuffer: 64 * 1024 * 1024 },
+    );
+    return JSON.parse(stdout);
+  } catch (error) {
+    // execFile's message embeds the full argv, bearer token included, so
+    // rebuild the error from the exit code and curl's last stderr line.
+    const stderr = String(error.stderr ?? '')
+      .trim()
+      .split('\n')
+      .pop();
+    throw new Error(
+      `GET ${path} failed (curl exit ${error.code ?? '?'})${stderr ? `: ${stderr}` : ''}`,
+    );
+  }
+}
+
+async function git(...args) {
+  const { stdout } = await execFileAsync('git', args, {
+    maxBuffer: 64 * 1024 * 1024,
+    timeout: 120_000,
+  });
+  return stdout;
+}
+
+// For one command at a time: fetch the merge base's commit and trees only,
+// and let `git diff` pull just the blobs it compares. A plain depth-1 fetch
+// would transfer the whole tree again, about 60 MiB, on every PR.
+const PARTIAL = [
+  '-c',
+  'extensions.partialClone=origin',
+  '-c',
+  'remote.origin.promisor=true',
+];
+
+/** Net test and production lines between the PR's merge base and its head. */
+export async function measure({ fetchJson, runGit, repo, baseSha, headSha }) {
+  const compare = await fetchJson(
+    `/repos/${repo}/compare/${baseSha}...${headSha}?per_page=1`,
+  );
+  const mergeBase = compare?.merge_base_commit?.sha;
+  if (!mergeBase) throw new Error('compare API returned no merge base');
+  let partial = false;
+  try {
+    await runGit('cat-file', '-e', `${mergeBase}^{commit}`);
+  } catch {
+    const fetch = ['fetch', '--no-tags', '--depth=1'];
+    try {
+      await runGit(
+        ...PARTIAL,
+        ...fetch,
+        '--filter=blob:none',
+        'origin',
+        mergeBase,
+      );
+      partial = true;
+    } catch {
+      await runGit(...fetch, 'origin', mergeBase);
+    }
+  }
+  try {
+    const numstat = await runGit(
+      ...(partial ? PARTIAL : []),
+      'diff',
+      '--numstat',
+      '--no-renames',
+      mergeBase,
+      headSha,
+      '--',
+      ...PACKAGES.map((name) => `packages/${name}`),
+    );
+    return { mergeBase, tallied: tally(parseNumstat(numstat)) };
+  } finally {
+    // The filtered fetch records its filter on the remote; drop it so later
+    // fetches in this checkout stay ordinary.
+    if (partial) {
+      await runGit(
+        'config',
+        '--unset',
+        'remote.origin.partialclonefilter',
+      ).catch(() => {});
+    }
+  }
+}
+
+async function main() {
+  const { GITHUB_TOKEN, BASE_SHA, HEAD_SHA, GITHUB_REPOSITORY } = process.env;
+  if (!GITHUB_TOKEN || !BASE_SHA || !HEAD_SHA || !GITHUB_REPOSITORY) {
+    console.log(
+      '::warning::test growth: BASE_SHA, HEAD_SHA, GITHUB_REPOSITORY or ' +
+        'GITHUB_TOKEN missing; skipping the check',
+    );
+    return;
+  }
+  try {
+    const { mergeBase, tallied } = await measure({
+      fetchJson: (path) => curlJson(path, GITHUB_TOKEN),
+      runGit: git,
+      repo: GITHUB_REPOSITORY,
+      baseSha: BASE_SHA,
+      headSha: HEAD_SHA,
+    });
+    const summary = renderSummary(tallied);
+    console.log(`Merge base ${mergeBase.slice(0, 12)}\n\n${summary}`);
+    if (process.env.GITHUB_STEP_SUMMARY) {
+      appendFileSync(process.env.GITHUB_STEP_SUMMARY, `${summary}\n`);
+    }
+    const annotation = renderAnnotation(tallied);
+    if (annotation) console.log(annotation);
+  } catch (error) {
+    // One line: an annotation ends at the first newline.
+    const reason = String(error.message).split('\n')[0];
+    console.log(
+      `::warning::test growth check could not run (${reason}); skipping it`,
+    );
+  }
+}
+
+if (
+  process.argv[1] &&
+  import.meta.url === pathToFileURL(process.argv[1]).href
+) {
+  await main();
+}
diff --git a/.github/scripts/check-test-growth.test.mjs b/.github/scripts/check-test-growth.test.mjs
new file mode 100644
index 00000000000..80a98de02be
--- /dev/null
+++ b/.github/scripts/check-test-growth.test.mjs
@@ -0,0 +1,216 @@
+import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
+import { dirname, join } from 'node:path';
+import test from 'node:test';
+import { fileURLToPath } from 'node:url';
+
+import {
+  FLAG_THRESHOLD,
+  classify,
+  curlJson,
+  measure,
+  packageOf,
+  parseNumstat,
+  renderAnnotation,
+  renderSummary,
+  tally,
+} from './check-test-growth.mjs';
+
+const repoRoot = join(dirname(fileURLToPath(import.meta.url)), '..', '..');
+
+test('classifies test, production and other files', () => {
+  const cases = {
+    'packages/core/src/a.test.ts': 'test',
+    'packages/cli/src/ui/App.test.tsx': 'test',
+    'packages/core/src/a.spec.ts': 'test',
+    'packages/core/src/tools/shell.test-helper.ts': 'test',
+    'packages/core/src/x/case.fixtures.json': 'test',
+    'packages/core/src/utils/testUtils.ts': 'test',
+    'packages/core/test-setup.ts': 'test',
+    'packages/core/src/__tests__/a.ts': 'test',
+    'packages/cli/src/__snapshots__/App.test.tsx.snap': 'test',
+    'packages/core/src/test-utils/mock-tool.ts': 'test',
+    'packages/cli/src/commands/review/lib/test-utils.ts': 'test',
+    'packages/core/src/lsp/__e2e__/lsp-e2e-test.ts': 'test',
+    'packages/web-shell/client/e2e/utils/mockDaemon.ts': 'test',
+    'packages/web-shell/client/test/setup.ts': 'test',
+    'packages/core/src/core/client.ts': 'production',
+    'packages/web-shell/client/src/App.tsx': 'production',
+    'packages/cli/src/index.mjs': 'production',
+    'packages/core/src/config/settings.schema.ts': 'other',
+    'packages/core/src/generated/git-commit.ts': 'other',
+    'packages/core/src/x.generated.ts': 'other',
+    'packages/core/package.json': 'other',
+    'packages/web-shell/client/src/app.css': 'other',
+    'packages/core/README.md': 'other',
+  };
+  for (const [path, kind] of Object.entries(cases)) {
+    assert.equal(classify(path), kind, path);
+  }
+});
+
+test('counts only core, cli and web-shell', () => {
+  assert.equal(packageOf('packages/core/src/a.ts'), 'core');
+  assert.equal(packageOf('packages/web-shell/client/src/a.ts'), 'web-shell');
+  assert.equal(packageOf('packages/sdk-typescript/src/a.ts'), null);
+  assert.equal(packageOf('scripts/build.js'), null);
+});
+
+test('tallies numstat per package, skipping binary and other files', () => {
+  const numstat = [
+    '120\t20\tpackages/core/src/a.test.ts',
+    '30\t5\tpackages/core/src/a.ts',
+    '-\t-\tpackages/cli/assets/logo.png',
+    '40\t0\tpackages/cli/src/b.test.tsx',
+    '9\t1\tpackages/cli/package.json',
+    '7\t2\tpackages/sdk-typescript/src/c.test.ts',
+    '',
+  ].join('\n');
+  const entries = parseNumstat(numstat);
+  assert.equal(entries.length, 5);
+  assert.deepEqual(tally(entries), {
+    byPackage: {
+      core: {
+        test: { added: 120, deleted: 20 },
+        production: { added: 30, deleted: 5 },
+      },
+      cli: {
+        test: { added: 40, deleted: 0 },
+        production: { added: 0, deleted: 0 },
+      },
+      'web-shell': {
+        test: { added: 0, deleted: 0 },
+        production: { added: 0, deleted: 0 },
+      },
+    },
+    total: {
+      test: { added: 160, deleted: 20 },
+      production: { added: 30, deleted: 5 },
+    },
+  });
+});
+
+test('flags at the threshold of net test lines, not below', () => {
+  const withNet = (n) =>
+    tally([
+      { added: n + 100, deleted: 100, path: 'packages/core/src/a.test.ts' },
+    ]);
+  assert.equal(FLAG_THRESHOLD, 2000);
+
+  const below = withNet(FLAG_THRESHOLD - 1);
+  assert.equal(renderAnnotation(below), null);
+  assert.doesNotMatch(renderSummary(below), /net test lines, at or above/);
+
+  const at = withNet(FLAG_THRESHOLD);
+  assert.match(
+    renderAnnotation(at),
+    /^::warning title=Test growth::This PR adds 2,000 net test lines/,
+  );
+  assert.match(renderSummary(at), /\| core \| \+2,100 \/ −100 \(net \+2,000\)/);
+  assert.match(
+    renderSummary(at),
+    /2,000 net test lines, at or above the 2,000-line flag/,
+  );
+});
+
+test('measures from the merge base, fetching it only when missing', async () => {
+  const [base, head, mergeBase] = ['b', 'h', 'm'].map((c) => c.repeat(40));
+  const run = async ({ present, partialFails = false }) => {
+    const calls = [];
+    const result = await measure({
+      repo: 'QwenLM/qwen-code',
+      baseSha: base,
+      headSha: head,
+      fetchJson: async (path) => {
+        assert.equal(
+          path,
+          `/repos/QwenLM/qwen-code/compare/${base}...${head}?per_page=1`,
+        );
+        return { merge_base_commit: { sha: mergeBase } };
+      },
+      runGit: async (...args) => {
+        calls.push(args.join(' '));
+        if (args[0] === 'cat-file' && !present) throw new Error('missing');
+        if (partialFails && args.includes('--filter=blob:none')) {
+          throw new Error('no partial clone');
+        }
+        // The diff must start at the merge base, not the base tip.
+        if (args.includes('diff')) return '3\t1\tpackages/core/src/a.test.ts\n';
+        return '';
+      },
+    });
+    assert.deepEqual(result.tallied.total.test, { added: 3, deleted: 1 });
+    return calls;
+  };
+  const PARTIAL =
+    '-c extensions.partialClone=origin -c remote.origin.promisor=true';
+  const DIFF = `diff --numstat --no-renames ${mergeBase} ${head} -- packages/core packages/cli packages/web-shell`;
+
+  assert.deepEqual(await run({ present: true }), [
+    `cat-file -e ${mergeBase}^{commit}`,
+    DIFF,
+  ]);
+  assert.deepEqual(await run({ present: false }), [
+    `cat-file -e ${mergeBase}^{commit}`,
+    `${PARTIAL} fetch --no-tags --depth=1 --filter=blob:none origin ${mergeBase}`,
+    `${PARTIAL} ${DIFF}`,
+    'config --unset remote.origin.partialclonefilter',
+  ]);
+  assert.deepEqual(
+    (await run({ present: false, partialFails: true })).slice(2),
+    [`fetch --no-tags --depth=1 origin ${mergeBase}`, DIFF],
+  );
+});
+
+test('ci.yml runs the check in lint_and_static on pull requests', () => {
+  const ci = readFileSync(join(repoRoot, '.github/workflows/ci.yml'), 'utf8');
+  const jobStart = ci.indexOf('\n  lint_and_static:');
+  const jobEnd = ci.indexOf('\n  test_macos:', jobStart);
+  assert.ok(jobStart > 0 && jobEnd > jobStart, 'lint_and_static job not found');
+  const job = ci.slice(jobStart, jobEnd);
+
+  const step = job.indexOf("- name: 'Report test growth'");
+  assert.ok(step > 0, 'test growth step missing');
+  const stepBlock = job.slice(step, job.indexOf('\n      - name:', step + 1));
+  for (const expected of [
+    "github.event_name == 'pull_request'",
+    "skip_ci != 'true'",
+    'github.event.pull_request.base.sha',
+    'github.event.pull_request.head.sha',
+    'node .github/scripts/check-test-growth.mjs',
+  ]) {
+    assert.ok(stepBlock.includes(expected), `step must include ${expected}`);
+  }
+  assert.ok(
+    step < job.indexOf("- name: 'Install dependencies'"),
+    'the check needs no dependencies and must run before the install',
+  );
+
+  for (const list of ['HELPER_TESTS_DEP_FREE', 'HELPER_TESTS']) {
+    const line = ci.split('\n').find((l) => l.trim().startsWith(`${list}:`));
+    assert.ok(
+      line?.includes('.github/scripts/check-test-growth.test.mjs'),
+      `${list} must run this test`,
+    );
+  }
+});
+
+test('API errors never carry the token', async () => {
+  const failing = async () => {
+    throw Object.assign(
+      new Error('Command failed: curl -H Authorization: Bearer secret-token'),
+      {
+        code: 22,
+        stderr: 'curl: (22) The requested URL returned error: 401\n',
+      },
+    );
+  };
+  await assert.rejects(
+    curlJson('/repos/o/r/compare/a...b', 'secret-token', failing),
+    (error) => {
+      assert.doesNotMatch(error.message, /secret-token/);
+      assert.match(error.message, /curl exit 22\): curl: \(22\).*401$/);
+      return true;
+    },
+  );
+});
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d9ddfaa288f..9eacc72167a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -87,8 +87,8 @@ env:
   # re-runs every suite after `npm ci`, and a push to main always classifies
   # `full` (classify_pr computes a profile only for pull_request), so what
   # the fast lane skips is still re-checked post-merge.
-  HELPER_TESTS_DEP_FREE: '.github/scripts/pr-safety-precheck.test.mjs .github/scripts/cap-release-notes.test.mjs .github/scripts/ci/classify-profile.test.mjs .github/scripts/ci/classify-platform-sensitivity.test.mjs .github/scripts/ci/classify-pr-profile.test.mjs .github/scripts/upsert-bot-comment.test.mjs .github/scripts/ci/main-failure-signature.test.mjs .github/scripts/dsw-swe-verified/make-manifest.test.mjs .github/scripts/dsw-swe-verified/make-terminal-bench-manifest.test.mjs .github/scripts/update-ecs-runner-qwen-workflow.test.mjs .github/scripts/web-shell-visuals-compose.test.mjs .github/scripts/serve-ab-diff.test.mjs .github/scripts/serve-ab-drive.test.mjs .github/scripts/autofix-status-heartbeat.test.mjs .github/scripts/check-disk-floor.test.mjs .github/scripts/check-lint-gate-freshness.test.mjs .github/scripts/review-runner-schedule.test.mjs .github/scripts/ecs-runner/qwen-docker-cleanup.test.mjs'
-  HELPER_TESTS: '.github/scripts/pr-safety-precheck.test.mjs .github/scripts/cap-release-notes.test.mjs .github/scripts/ci/classify-profile.test.mjs .github/scripts/ci/classify-platform-sensitivity.test.mjs .github/scripts/ci/classify-pr-profile.test.mjs .github/scripts/upsert-bot-comment.test.mjs .github/scripts/ci/main-failure-signature.test.mjs .github/scripts/classify-release-notes.test.mjs .github/scripts/dsw-swe-verified/make-manifest.test.mjs .github/scripts/dsw-swe-verified/make-terminal-bench-manifest.test.mjs .github/scripts/resolve-sandbox-image.test.mjs .github/scripts/update-ecs-runner-qwen-workflow.test.mjs .github/scripts/web-shell-visuals-publish.test.mjs .github/scripts/web-shell-visuals-compose.test.mjs .github/scripts/serve-ab-diff.test.mjs .github/scripts/serve-ab-drive.test.mjs .github/scripts/qwen-triage-workflow.test.mjs .github/scripts/assign-issue-owner.test.mjs .github/scripts/auto-minimize-spam.test.mjs .github/scripts/ci-runner-routing.test.mjs .github/scripts/autofix-status-heartbeat.test.mjs .github/scripts/assign-pr-owner.test.mjs .github/scripts/check-disk-floor.test.mjs .github/scripts/check-lint-gate-freshness.test.mjs .github/scripts/ci-disk-pressure.test.mjs .github/scripts/e2e-build.test.mjs integration-tests/concurrent-runner/export-html-from-chatrecord-jsonl.test.mjs .github/scripts/review-runner-schedule.test.mjs .github/scripts/ecs-runner/qwen-docker-cleanup.test.mjs .github/scripts/ecs-runner/review-scratch-cleanup.test.mjs'
+  HELPER_TESTS_DEP_FREE: '.github/scripts/pr-safety-precheck.test.mjs .github/scripts/cap-release-notes.test.mjs .github/scripts/ci/classify-profile.test.mjs .github/scripts/ci/classify-platform-sensitivity.test.mjs .github/scripts/ci/classify-pr-profile.test.mjs .github/scripts/upsert-bot-comment.test.mjs .github/scripts/ci/main-failure-signature.test.mjs .github/scripts/dsw-swe-verified/make-manifest.test.mjs .github/scripts/dsw-swe-verified/make-terminal-bench-manifest.test.mjs .github/scripts/update-ecs-runner-qwen-workflow.test.mjs .github/scripts/web-shell-visuals-compose.test.mjs .github/scripts/serve-ab-diff.test.mjs .github/scripts/serve-ab-drive.test.mjs .github/scripts/autofix-status-heartbeat.test.mjs .github/scripts/check-disk-floor.test.mjs .github/scripts/check-lint-gate-freshness.test.mjs .github/scripts/review-runner-schedule.test.mjs .github/scripts/ecs-runner/qwen-docker-cleanup.test.mjs .github/scripts/check-test-growth.test.mjs'
+  HELPER_TESTS: '.github/scripts/pr-safety-precheck.test.mjs .github/scripts/cap-release-notes.test.mjs .github/scripts/ci/classify-profile.test.mjs .github/scripts/ci/classify-platform-sensitivity.test.mjs .github/scripts/ci/classify-pr-profile.test.mjs .github/scripts/upsert-bot-comment.test.mjs .github/scripts/ci/main-failure-signature.test.mjs .github/scripts/classify-release-notes.test.mjs .github/scripts/dsw-swe-verified/make-manifest.test.mjs .github/scripts/dsw-swe-verified/make-terminal-bench-manifest.test.mjs .github/scripts/resolve-sandbox-image.test.mjs .github/scripts/update-ecs-runner-qwen-workflow.test.mjs .github/scripts/web-shell-visuals-publish.test.mjs .github/scripts/web-shell-visuals-compose.test.mjs .github/scripts/serve-ab-diff.test.mjs .github/scripts/serve-ab-drive.test.mjs .github/scripts/qwen-triage-workflow.test.mjs .github/scripts/assign-issue-owner.test.mjs .github/scripts/auto-minimize-spam.test.mjs .github/scripts/ci-runner-routing.test.mjs .github/scripts/autofix-status-heartbeat.test.mjs .github/scripts/assign-pr-owner.test.mjs .github/scripts/check-disk-floor.test.mjs .github/scripts/check-lint-gate-freshness.test.mjs .github/scripts/ci-disk-pressure.test.mjs .github/scripts/e2e-build.test.mjs integration-tests/concurrent-runner/export-html-from-chatrecord-jsonl.test.mjs .github/scripts/review-runner-schedule.test.mjs .github/scripts/ecs-runner/qwen-docker-cleanup.test.mjs .github/scripts/ecs-runner/review-scratch-cleanup.test.mjs .github/scripts/check-test-growth.test.mjs'
   # The growth ratchet and its vitest mirror compare each workflow against
   # the PR's base commit to tell "this PR grew the file" apart from "the
   # baseline went stale on main" (#9904). Wired once here so every lane
@@ -1097,6 +1097,17 @@ jobs:
           HEAD_SHA: '${{ github.event.pull_request.head.sha }}'
         run: 'node .github/scripts/check-lint-gate-freshness.mjs'
 
+      # Advisory test-growth summary and flag; see the script header.
+      - name: 'Report test growth'
+        if: "${{ needs.classify_pr.outputs.skip_ci != 'true' && github.event_name == 'pull_request' }}"
+        continue-on-error: true
+        timeout-minutes: 5
+        env:
+          GITHUB_TOKEN: '${{ secrets.GITHUB_TOKEN }}'
+          BASE_SHA: '${{ github.event.pull_request.base.sha }}'
+          HEAD_SHA: '${{ github.event.pull_request.head.sha }}'
+        run: 'node .github/scripts/check-test-growth.mjs'
+
       # Avoid setup-node downloads on ECS, where nodejs.org may be unreachable
       # through the egress proxy; reuse the machine's Node instead.
       - name: 'Set up Node.js 22.x (hosted)'