diff --git a/scripts/qa-all-layer-switches.mjs b/scripts/qa-all-layer-switches.mjs
index a6f5f6d61..e9c32683f 100644
--- a/scripts/qa-all-layer-switches.mjs
+++ b/scripts/qa-all-layer-switches.mjs
@@ -1,11 +1,16 @@
-import { spawnSync } from 'node:child_process';
+import { execFileSync, spawnSync } from 'node:child_process';
+import { createHash } from 'node:crypto';
 import { mkdirSync, mkdtempSync, writeFileSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { join, resolve } from 'node:path';
 import { fileURLToPath } from 'node:url';
 import assert from 'node:assert/strict';
+import puppeteer from 'puppeteer';
 import { APPLICATION_LAYER_DIRECTORY } from '../src/app/layers/directory.js';
 
+// Runs every browser scenario against one keyless local preview and writes
+// <output>/acceptance.json plus one log per scenario.
+
 const base = new URL(process.argv[2]);
 if (
   !['127.0.0.1', 'localhost'].includes(base.hostname) ||
@@ -18,6 +23,46 @@ const output = process.argv[3]
   ? resolve(process.argv[3])
   : mkdtempSync(join(tmpdir(), 'gev-layer-switch-'));
 mkdirSync(output, { recursive: true });
+
+// Fail once, with the fix, instead of once per scenario.
+let chrome;
+try {
+  const browser = await puppeteer.launch({ headless: true });
+  chrome = await browser.version();
+  await browser.close();
+} catch (error) {
+  console.error(
+    'Puppeteer cannot start Chrome: ' +
+      String(error?.message)
+        .split('\n')[0]
+        .replace(/ This can occur.*/, '') +
+      '\nPoint PUPPETEER_EXECUTABLE_PATH at an installed Chrome, for example\n' +
+      '  PUPPETEER_EXECUTABLE_PATH="/Applications/Google Chrome.app/Contents/MacOS/Google Chrome"\n' +
+      'or download the pinned build with `npx puppeteer browsers install chrome`.',
+  );
+  process.exit(2);
+}
+try {
+  const response = await fetch(base.origin + '/', {
+    signal: AbortSignal.timeout(10000),
+  });
+  if (!response.ok) throw Error('HTTP ' + response.status);
+} catch (error) {
+  console.error(
+    'No preview answers at ' + base.origin + ' (' + error.message + ').',
+  );
+  process.exit(2);
+}
+const root = fileURLToPath(new URL('..', import.meta.url));
+const git = (...args) =>
+  execFileSync('git', args, { cwd: root, encoding: 'utf8' });
+// Other work may change the tree while the run lasts; record both ends.
+const dirty = () =>
+  git('status', '--porcelain')
+    .split('\n')
+    .filter(Boolean)
+    .map((line) => line.slice(3));
+const dirtyFiles = dirty();
 const runs = [
   ['engine-switch', ['earthquakes']],
   ['director-engine-switch', []],
@@ -65,9 +110,32 @@ assert.deepEqual(
   APPLICATION_LAYER_DIRECTORY.map((l) => l.id).sort(),
   'Every catalog layer must have a browser scenario',
 );
-const report = [];
+const scenarios = [];
+const report = {
+  commit: git('rev-parse', 'HEAD').trim(),
+  dirty: dirtyFiles.length > 0,
+  dirtyFiles,
+  dirtyFilesAtEnd: null,
+  chrome,
+  puppeteerExecutable: process.env.PUPPETEER_EXECUTABLE_PATH || null,
+  node: process.version,
+  platform: process.platform + ' ' + process.arch,
+  baseUrl: base.origin,
+  startedAt: new Date().toISOString(),
+  finishedAt: null,
+  layers: ids,
+  passed: 0,
+  failed: 0,
+  scenarios,
+};
+const save = () =>
+  writeFileSync(
+    join(output, 'acceptance.json'),
+    JSON.stringify(report, null, 2) + '\n',
+  );
 for (const [name, layers, flag] of runs) {
   const label = name + (flag ?? '');
+  const script = 'scripts/qa-' + name + '.mjs';
   const args =
     name === 'w2-imagery'
       ? [
@@ -80,40 +148,49 @@ for (const [name, layers, flag] of runs) {
         ]
       : [base.origin, ...(flag ? [flag] : [])];
   const start = Date.now();
-  const run = spawnSync(
-    process.execPath,
-    [fileURLToPath(new URL('./qa-' + name + '.mjs', import.meta.url)), ...args],
-    {
-      encoding: 'utf8',
-      timeout: 240000,
-      maxBuffer: 8388608,
-      env: { ...process.env, GOOGLE_MAPS_API_KEY: '', CESIUM_ION_TOKEN: '' },
-    },
-  );
-  const ok = run.status === 0;
-  writeFileSync(
-    join(output, label + '.log'),
-    (run.stdout || '') + (run.stderr || '') + (run.error?.message || ''),
-  );
-  report.push({
-    label,
-    layers,
-    ok,
-    seconds: Math.round((Date.now() - start) / 1000),
+  const run = spawnSync(process.execPath, [join(root, script), ...args], {
+    encoding: 'utf8',
+    timeout: 240000,
+    maxBuffer: 8388608,
+    env: { ...process.env, GOOGLE_MAPS_API_KEY: '', CESIUM_ION_TOKEN: '' },
   });
-  writeFileSync(
-    join(output, 'summary.json'),
-    JSON.stringify({ ids, report }, null, 2) + '\n',
-  );
-  console.log(ok ? 'PASS' : 'FAIL', label, report.at(-1).seconds);
+  const status =
+    run.status === 0
+      ? 'pass'
+      : run.error?.code === 'ETIMEDOUT'
+        ? 'timeout'
+        : 'fail';
+  const log =
+    (run.stdout || '') + (run.stderr || '') + (run.error?.message || '');
+  writeFileSync(join(output, label + '.log'), log);
+  scenarios.push({
+    label,
+    script,
+    args: args.map((arg) =>
+      arg.startsWith(output) ? '<output>' + arg.slice(output.length) : arg,
+    ),
+    layers,
+    status,
+    exitCode: run.status,
+    seconds: Math.round((Date.now() - start) / 100) / 10,
+    log: label + '.log',
+    logSha256: createHash('sha256').update(log).digest('hex'),
+  });
+  report.passed = scenarios.filter((row) => row.status === 'pass').length;
+  report.failed = scenarios.length - report.passed;
+  save();
+  console.log(status.toUpperCase(), label, scenarios.at(-1).seconds);
 }
+report.finishedAt = new Date().toISOString();
+report.dirtyFilesAtEnd = dirty();
+save();
 console.log(
   ids.length +
     ' layers, ' +
-    report.filter((row) => row.ok).length +
+    report.passed +
     '/' +
     runs.length +
     ' browser scenarios. ' +
-    output,
+    join(output, 'acceptance.json'),
 );
-if (report.some((row) => !row.ok)) process.exitCode = 1;
+if (report.failed) process.exitCode = 1;