browser-use/browser-harness

Let Claude Code, Codex or Cursor use your real Chrome, logged in as you. One prompt to set up. Open source, MIT.

Browser Harness – What It Is

Browser Harness is an open‑source bridge that lets large‑language‑model coding agents (Claude Code, Codex, Cursor, etc.) control a real Chrome browser through the Chrome DevTools Protocol (CDP). By installing the Python package and giving the agent a one‑line setup prompt, the agent can open pages, click, type, read content, and download files while staying logged in with the user’s own browser profile.

How It Works

  1. Installation & Connection – Run the provided install.md script (or the one‑line prompt) which installs the browser‑harness Python package (via uv) and registers a skill (browser‑harness skill). The script opens Chrome’s remote‑debugging page (chrome://inspect/#remote-debugging) and asks the user to enable remote debugging.
  2. Skill Definition – SKILL.md describes the high‑level workflow the agent should follow (open a page, locate elements, click, etc.).
  3. Agent‑Generated Helpers – When the agent needs a new helper function, it writes the code into its own workspace (agent_helpers.py). Those helpers become reusable for later tasks, allowing the harness to improve over time.
  4. MCP Server – The optional browser‑harness‑mcp component exposes the browser‑control commands as MCP tools over stdio, so any MCP‑compatible client (Claude Code, Devin, Cursor) can drive the browser without re‑implementing CDP logic.
  5. Scaling – For heavy workloads, users can switch to Browser Use Cloud, which runs many headless browsers in parallel with extra features like proxies, stealth mode, and CAPTCHA solving.

What You Can Do With It

  • Automate personal web tasks – e.g., download the latest 20 videos from an X (Twitter) profile while staying logged in.
  • Scrape data behind authentication – agents can navigate sites that require cookies or login sessions because they use the user’s actual Chrome profile.
  • Generate reusable automation helpers – as the agent encounters new patterns, it writes helper functions that become part of its toolbox.
  • Run at scale – via Browser Use Cloud for parallel browsers, useful for batch processing or testing.

Who Might Use It

  • Developers building AI‑augmented automation – want an LLM to interact with real web pages safely.
  • Product teams prototyping web‑agent workflows – quickly test how an agent can perform UI actions.
  • Researchers studying agent‑driven web interaction – need a reproducible, open‑source harness.

Getting Started (Brief)

# Using uv (recommended) with Python 3.12
uv pip install browser-harness
# Then paste the one‑line setup prompt into your coding agent

The agent will guide you through enabling remote debugging and will register the skill.

License

MIT – free for personal, commercial, or research use.

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