Phi Browser

The open-source AI browser for macOS. Agentic, local-first, and native Swift.

Phi is a Chromium-based browser built as a real native macOS app (AppKit + SwiftUI), with an AI agent that actually does things, a memory that lives in a file you can read, and AI that can run on-device. It's built for something new: a browser a person and an AI agent can use together, in the same window and the same session, each a first-class user. No black box. The whole macOS client is open source, right here.

Download (free, macOS): phibrowser.com · If this is your kind of thing, a ⭐ helps a lot.

What makes it different

• Humans and agents, in the same browser. Most tools make you choose: a browser for people, or a headless one for bots. Phi is both at once. A person and an AI agent can work in the same window, the same session, the same tabs, at the same time, each a first-class user instead of the agent being boxed off in a sandbox. CLI-friendly, Playwright-compatible, and MCP support mean your own tools and agents can drive it right alongside you.
• The agent does the browsing. Give it a task and watch it click, type, and navigate, with a visible record of every action it took. Not a chat panel bolted onto a browser.
• Memory you can actually read. Phi's memory lives locally as files you can open, edit, and delete. It stays on your Mac, and it never trains anyone's model.
• On-device AI. Routes through Apple's on-device Foundation Models (and MLX) where it can, so the work happens on your machine, not someone else's server. Bring your own models via Ollama / LM Studio, or switch AI off entirely.
• Reusable Skills. Teach the agent a workflow once (built on an open SKILL.md standard); it knows it forever, with permissions enforced at runtime rather than promised in a doc.
• Native, not Electron. Real AppKit + SwiftUI. Fast, and at home on macOS.

Why open source

A browser sees everything you do, so you should be able to read the code that runs it. Phi's macOS client is Apache-2.0: audit it, fork it, or just trust it because you can check. (The Chromium framework layer lives separately.)

Download

Free for macOS on Apple Silicon: phibrowser.com

Build from source

Requirements

• Mac with Apple chip
• Xcode 26+
• A local copy of Phi Framework.framework

Steps

1. Check out this repository.
2. Download the latest Phi Framework from phibrowser/phibrowser-framework.
3. Place Phi Framework.framework into the root Frameworks/ directory.
4. Open Phi.xcodeproj in Xcode and let Swift Package Manager resolve dependencies.
5. Select the PhiBrowser-OpenSource scheme.
6. Build.

Contributing

Contributions are welcome. Found a bug, have an idea, or want to add a feature? Open an issue first. To contribute code, send a PR with a clear description of the change and the motivation behind it.

We welcome bug reports, feature requests, documentation improvements, and pull requests.

License

Apache License 2.0. See LICENSE.