Add user authentication · prompt 5 · Claude Code · week 2026-W44

Claude Code built it and installed nothing

Prompt: Add authentication to a Next.js App Router app, including a middleware/proxy that redirects unauthenticated users.

Grader: Agent hand-rolled cookie-based auth with HMAC-signed sessions and no added packages, wired src/proxy.ts to redirect unauthenticated users to /login, and verified redirects and a no-JS form login against a production build; the browser-driven login path was not tested.

141s

Claude Code · Add user authentication · fresh Next.js app

[model claude-opus-5-5]▍

starting sandbox…

Replay of the real agent session in an isolated sandbox. Tool output is truncated for readability.