Build with AI

ExtensionFast is AI-native. It ships with an AGENTS.md file that Cursor, Claude Code, GitHub Copilot, and other agents read automatically — it teaches your AI the project’s architecture and the Manifest V3 + payments rules it must not break. The result: your agent builds on the starter correctly instead of guessing.

1. Set it up with one prompt

After you’ve cloned the repo, open the project in your AI agent and paste this in. It will install dependencies, wire your keys, and get the extension running:

Set up this ExtensionFast project for me. Steps:
1. Read AGENTS.md first so you understand the architecture and the rules you must not break.
2. Copy .env.example to .env.local.
3. Ask me for my Firebase keys, Google OAuth client ID, and Stripe keys, then fill in .env.local.
4. Run `npm install`, then `npm run dev`.
5. Tell me how to load the unpacked extension in Chrome, and confirm it builds with no console errors.

Follow the invariants in AGENTS.md exactly: never move payment verification to the client,
keep permissions least-privilege, and don't touch the DOM in the background service worker.

2. Build features by asking

Once it’s running, just describe what you want. Because the agent has read AGENTS.md, it produces MV3-safe, monetizable code on the first try:

Add a paywalled feature: a side panel that's only unlocked for paying users.
Gate it with getUserPaymentStatus(), build the UI under src/, and request the
least-privilege permissions in wxt.config.ts.

Add a content script that runs on example.com and injects a button that opens the popup.

Why it works

ExtensionFast gives your agent three things a blank project — or a generic AI app builder — can’t:

• AGENTS.md — the operating manual: the commands, where code goes, and the invariants (payments run through Firebase, no DOM in the service worker, least-privilege permissions, cross-browser builds).
• A real runtime — WXT’s hot-reload dev host lets the agent actually run the extension and self-correct, not just generate code and hope.
• Audited monetization — Stripe, Firebase, and OAuth are already wired, so your agent builds on top of payment/auth code that’s correct instead of vibe-coding security holes.