I've been working on a side project — a web app built on React 19, TypeScript, MUI on the frontend and Node.js/Express with Firebase/Firestore on the backend, deployed on Cloud Run. The project is at a stage where there's real code, real data, and real users, which makes me much more careful about what I let an AI assistant touch without oversight. GitHub Copilot (and AI coding assistants in general) are genuinely useful, but out of the box they have no knowledge of your project's conventions, your architecture boundaries, or which quality concerns actually matter. Ask it to "fix the login page" and it might improve the UI while quietly bypassing an auth check. Ask it to "add a new field to the database" and it won't know whether existing records need a migration. What I wanted was something closer to a team of specialists — each one with deep knowledge of their domain — that I could invoke by name, with consistent behaviour across every session....