diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 4fecc6e65b..7f03c87929 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -171,6 +171,7 @@ jobs:
       - run: cd workers/agent-runtime && npm ci --include=dev
       - run: npm run verify:moltbot-tools
       - run: npm run verify:litellm-patch-runner
+      - run: npm run verify:readme-invariants
       # These node:test files lived only in the retired all-in-one job.
       - name: Run agent service tests
         run: |
diff --git a/README.md b/README.md
index f898dc2e6d..8557ff1101 100644
--- a/README.md
+++ b/README.md
@@ -7,7 +7,7 @@
 Bring your workflow and your agents.<br/>
 Your team works with them in one pod.
 
-**[Try the cloud agent →](https://commonly.me)** &nbsp;&nbsp;&nbsp; **[Bring your own →](#bring-your-own)**
+**[Try the cloud agent →](https://commonly.me)** &nbsp;&nbsp;&nbsp; **[Bring your own →](#bring-your-own)** &nbsp;&nbsp;&nbsp; **[Discord →](https://discord.gg/NsS3fzsJDw)**
 
 [![Discord](https://img.shields.io/badge/Discord-join%20the%20community-5865F2?logo=discord&logoColor=white)](https://discord.gg/NsS3fzsJDw) &nbsp; [Join the community](https://discord.gg/NsS3fzsJDw)
 
diff --git a/package.json b/package.json
index b5b87ab584..92de278f15 100644
--- a/package.json
+++ b/package.json
@@ -19,6 +19,7 @@
     "verify:litellm-patch-runner": "node scripts/verify-litellm-patch-runner.js",
     "verify:numbered-rules": "node scripts/verify-numbered-rules.js",
     "verify:ax-audit-numbering": "node scripts/verify-ax-audit-numbering.js",
+    "verify:readme-invariants": "node scripts/verify-readme-invariants.js && node scripts/verify-readme-invariants.js --self-test",
     "prepare": "husky"
   },
   "devDependencies": {
diff --git a/scripts/verify-readme-invariants.js b/scripts/verify-readme-invariants.js
new file mode 100644
index 0000000000..19120f1500
--- /dev/null
+++ b/scripts/verify-readme-invariants.js
@@ -0,0 +1,146 @@
+#!/usr/bin/env node
+/**
+ * README invariant check.
+ *
+ * The official Discord invite went into the README with a top badge on 07-19
+ * (#694, #695). The 10-23 rewrite (#2477) dropped the badge, so Discord
+ * survived only as a footer link, and nothing noticed until Sam did. This check
+ * is the thing that notices: it fails, naming each missing item, when the
+ * README stops carrying what a visitor needs.
+ *
+ * The rules are below. To change them, edit RULES here and record the reason in
+ * the README benchmark brief (TASK-422), which is where the README's
+ * structure is argued. Do not add a rule without a reason there.
+ *
+ * Usage: node scripts/verify-readme-invariants.js [path]
+ *        node scripts/verify-readme-invariants.js --self-test
+ */
+
+const fs = require('fs');
+const path = require('path');
+
+const DEFAULT_FILE = path.join(__dirname, '..', 'README.md');
+const TOP_LINES = 40;
+const DISCORD_INVITE = 'https://discord.gg/NsS3fzsJDw';
+// The bare host/path, for messages and self-test labels. Never used to match a URL.
+const DISCORD_LABEL = 'discord.gg/NsS3fzsJDw';
+
+// Compare parsed URLs, not substrings: `includes(url)` would accept
+// `https://evil.example/?x=https://discord.gg/NsS3fzsJDw`.
+function hasDiscordInvite(lines) {
+  const urls = lines.join('\n').match(/https?:\/\/[^\s)"'<>]+/g) || [];
+  const invite = new URL(DISCORD_INVITE);
+  return urls.some((raw) => {
+    try {
+      const url = new URL(raw);
+      return url.protocol === invite.protocol
+        && url.hostname === invite.hostname
+        && url.pathname === invite.pathname;
+    } catch (err) {
+      return false;
+    }
+  });
+}
+
+// Link targets are parsed, not matched as prefixes: a prefix test accepts
+// `https://docs.commonly.me@evil.example/` and `https://docs.commonly.me.evil.example/`.
+function linkTargets(lines) {
+  return [...lines.join('\n').matchAll(/\]\(([^)\s]+)/g)].map((m) => m[1]);
+}
+
+function isDocsTarget(target) {
+  if (target.startsWith('docs/')) return true;
+  try {
+    const url = new URL(target);
+    return url.protocol === 'https:' && url.hostname === 'docs.commonly.me';
+  } catch (err) {
+    return false;
+  }
+}
+
+// Each rule: a name a reader can act on, and a test over the README text.
+const RULES = [
+  {
+    name: `the Discord invite (${DISCORD_LABEL}) within the first ${TOP_LINES} lines`,
+    check: (lines) => hasDiscordInvite(lines.slice(0, TOP_LINES)),
+  },
+  {
+    name: 'a link to the docs',
+    check: (lines) => linkTargets(lines).some(isDocsTarget),
+  },
+  {
+    name: 'a link to the license (LICENSE)',
+    check: (lines) => /\]\((\.\/)?LICENSE\)/.test(lines.join('\n')),
+  },
+  {
+    name: 'a quickstart section or link',
+    check: (lines) => /^#{1,6} .*quick ?start/im.test(lines.join('\n'))
+      || /\]\([^)]*quickstart[^)]*\)/i.test(lines.join('\n')),
+  },
+];
+
+function checkReadme(text) {
+  const lines = text.split('\n');
+  return RULES.filter((rule) => !rule.check(lines)).map((rule) => `missing ${rule.name}`);
+}
+
+function selfTest() {
+  const complete = [
+    `[![Discord](https://img.shields.io/badge/chat-discord-blue)](${DISCORD_INVITE})`,
+    '## Quick Start',
+    '[Docs](docs/README.md) · [License](LICENSE)',
+  ].join('\n');
+  if (checkReadme(complete).length !== 0) {
+    throw new Error('self-test: a complete fixture was reported as missing something');
+  }
+
+  // A README without the invite must fail, and must name the invite.
+  const noInvite = complete.replace(DISCORD_INVITE, 'https://example.com');
+  const problems = checkReadme(noInvite);
+  if (!problems.some((p) => p.includes(DISCORD_LABEL))) {
+    throw new Error(`self-test: a README without the invite did not fail naming it: ${JSON.stringify(problems)}`);
+  }
+
+  // A docs link must resolve to the docs host, not merely start with it.
+  for (const bogus of ['https://docs.commonly.me@evil.example/', 'https://docs.commonly.me.evil.example/']) {
+    const fake = complete.replace('[Docs](docs/README.md)', `[Docs](${bogus})`);
+    if (!checkReadme(fake).some((p) => p.includes('a link to the docs'))) {
+      throw new Error(`self-test: a docs link to ${bogus} was accepted`);
+    }
+  }
+
+  // The invite carried in another host's query string is not the invite.
+  const lookalike = complete.replace(DISCORD_INVITE, `https://example.com/?u=${DISCORD_INVITE}`);
+  if (!checkReadme(lookalike).some((p) => p.includes(DISCORD_LABEL))) {
+    throw new Error('self-test: a lookalike URL carrying the invite was accepted');
+  }
+
+  // The invite past line 40 is a footer, not a top link: it must fail too.
+  const padded = `${'filler\n'.repeat(TOP_LINES)}${DISCORD_INVITE}\n## Quick Start\n[D](https://docs.commonly.me/quickstart)\n[L](LICENSE)`;
+  if (!checkReadme(padded).some((p) => p.includes(`within the first ${TOP_LINES} lines`))) {
+    throw new Error('self-test: an invite below the top lines was accepted');
+  }
+  console.log('readme invariants self-test: ok');
+}
+
+function main(argv) {
+  if (argv.includes('--self-test')) {
+    selfTest();
+    return 0;
+  }
+  const file = argv.find((a) => !a.startsWith('--')) || DEFAULT_FILE;
+  const problems = checkReadme(fs.readFileSync(file, 'utf8'));
+  if (problems.length > 0) {
+    console.error(`README invariants failed for ${path.relative(process.cwd(), file)}:`);
+    for (const p of problems) console.error(`  - ${p}`);
+    return 1;
+  }
+  console.log(`README invariants: ok (${RULES.length} rules)`);
+  return 0;
+}
+
+if (require.main === module) {
+  process.exitCode = main(process.argv.slice(2));
+}
+
+module.exports = { checkReadme, RULES, DISCORD_INVITE };