About

Built for the open web.

Benzo Agent is a browser-native autonomous agent. No cloud. No accounts. No telemetry. Just an extension that does useful things.

Why it exists

Most automation tools require a server, an account, and a subscription. They run on someone else's machine, need your credentials, and disappear when they shut down. We wanted the opposite: a tool that runs where you already are, uses what the browser already gives, and never phones home.

Benzo Agent is 21 files of vanilla JavaScript. No framework. No bundler. No dependencies. Every feature is built on native browser primitives — DOM, Web Workers, DevTools Protocol, MediaRecorder — and shipped as a Manifest V3 extension.

Design principles

  • Local-first. Default behavior makes zero network requests. Everything you do stays on your device.
  • Human-in-the-loop. The agent pauses before destructive actions. You approve every risky step.
  • Transparent. Every action is logged and visible in the timeline. You see exactly what the agent is doing.
  • No lock-in. MIT licensed. Fork it, audit it, extend it. The code is the product.

Tech stack

Manifest V3Service worker, side panel, content scripts
Chrome DevTools ProtocolScreenshot capture with viewport resize
MediaRecorder APIWebM/MP4 video with audio mixing
Isolated + MAIN worldsContent isolation with event guards
IndexedDB + StorageLocal persistence for runs and settings
Vanilla JSNo framework, no build step, no bundler

License

MIT. Use it for anything. Modify it. Ship it. Sell it. Just keep the copyright notice.

Give it a try.

Free, open source, works offline.

Download Docs