Replace local ai-agent-detection with @vercel/agent-readability

[molebox]

Summary

• Replaces local ai-agent-detection.ts with the shared @vercel/agent-readability package
• UA pattern updates now propagate from one place via version bumps
• Adds generateNotFoundMarkdown response for agents hitting non-existent docs URLs

Same approach as vercel/front#65649 and vercel/geistdocs#58.

Test plan

• AI agent hitting a valid docs URL gets markdown rewrite
• AI agent hitting a non-existent docs URL gets helpful not-found markdown
• Accept header content negotiation still works
• Build passes

🤖 Generated with Claude Code

[changeset-bot]

⚠️ No Changeset found

Latest commit: fd863ce

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[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Error		Apr 1, 2026 1:26pm
example-nextjs-workflow-webpack	Error		Apr 1, 2026 1:26pm
example-workflow	Error		Apr 1, 2026 1:26pm
workbench-astro-workflow	Error		Apr 1, 2026 1:26pm
workbench-express-workflow	Error		Apr 1, 2026 1:26pm
workbench-fastify-workflow	Error		Apr 1, 2026 1:26pm
workbench-hono-workflow	Error		Apr 1, 2026 1:26pm
workbench-nitro-workflow	Error		Apr 1, 2026 1:26pm
workbench-nuxt-workflow	Error		Apr 1, 2026 1:26pm
workbench-sveltekit-workflow	Error		Apr 1, 2026 1:26pm
workbench-vite-workflow	Error		Apr 1, 2026 1:26pm
workflow-docs	Error		Apr 1, 2026 1:26pm
workflow-swc-playground	Error		Apr 1, 2026 1:26pm

[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ 💻 Local Development	118	0	50	168
✅ 📦 Local Production	118	0	50	168
✅ 🐘 Local Postgres	118	0	50	168
Total	354	0	150	504

Details by Category

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ nextjs-turbopack-canary	59	0	25
✅ nextjs-webpack-canary	59	0	25

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ nextjs-turbopack-canary	59	0	25
✅ nextjs-webpack-canary	59	0	25

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ nextjs-turbopack-canary	59	0	25
✅ nextjs-webpack-canary	59	0	25

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: failure
• Local Dev: failure
• Local Prod: failure
• Local Postgres: failure
• Windows: failure

Check the workflow run for details.

[github-actions]

No benchmark result files found in benchmark-results

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	npm/​@​vercel/​agent-readability@​0.2.1

View full report

[vercel]

Not-found markdown response for AI agents returns HTTP 200 instead of HTTP 404, creating a soft 404 anti-pattern that misleads agents into treating "Page Not Found" content as valid page content.