## What is https://unchainedsky.com/unbrowser? **unbrowser** is an open-source, lightweight **MCP (Model Context Protocol) browser** built by **Unchained** — designed specifically for LLM agents (like AI coding assistants, browser agents, etc.). ### Key Features: - **One native binary** — no Chrome, Playwright, or heavy browser engine required. - **Stateful sessions** — supports cookies, forms, navigation, clicking, typing, and bounded JavaScript execution. - **BlockMaps** — a low-token representation of page structure (headings, links, buttons, forms, density) instead of dumping raw DOM into the LLM context window. - **32 MCP tools** exposed via `--mcp` flag. - **SSRF guard** built in for safety. - **Escalation-ready** — when a page truly needs a full Chrome browser (auth, extensions, human-in-the-loop), you can hand off to Unchained's full Chrome session. ### How It Works: You can run it locally: ``` unbrowser --mcp ``` Or use the hosted Streamable HTTP endpoint at `https://unchainedsky.com/unbrowser-mcp` for public/smoke-test pages. ### Live Scan Demos: The page also offers pre-built "fixed-source scans" that let you test unbrowser against real sites — e.g., news pages, crypto prices, developer docs, security advisories, research papers, startup launches, etc. — to see how well it handles them without needing a full Chrome session. ### Bottom Line: unbrowser is a **Chrome-free, agent-friendly browser** that gives LLMs web access without the overhead of a full browser engine. It's meant for quick, cheap page retrieval — and you escalate to a real browser only when necessary.