npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2026 – Pkg Stats / Ryan Hefner

real-browser-mcp

v1.2.1

Published

MCP server + Chrome extension that gives AI agents control of your real browser with existing sessions and logins

Readme


You ship a fix. Your agent says "done, please verify." You alt-tab to Chrome, navigate to the page, log in, click around, find the bug.

Your agent just wrote the code. It could also verify it. It already has your browser open right there. It just can't see it.

Now it can.


Quick Start

Two parts:

  • MCP server - runs on your machine, talks to your AI agent
  • Chrome extension - sits in your browser, executes the commands

1. Add the MCP server

Cursor (one click):

Or add manually in Cursor Settings > MCP > "Add new MCP server":

{
  "mcpServers": {
    "real-browser": {
      "command": "npx",
      "args": ["-y", "real-browser-mcp"]
    }
  }
}

Claude Desktop: Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows). Add the same JSON block.

Windsurf: Settings > MCP. Same config.

Any MCP-compatible client works.

2. Install the Chrome extension

Or load from source:

git clone https://github.com/ofershap/real-browser-mcp.git
  1. Open chrome://extensions and enable Developer mode (toggle in the top right)
  2. Click Load unpacked and select the extension/ folder from the cloned repo

Click the Real Browser MCP icon in your toolbar.

Green dot = connected. Gray = waiting for server.

Done. Your agent can see your browser.


How Others Compare

| | Real Browser MCP | Playwright MCP | Chrome DevTools MCP | |---|---|---|---| | Uses your existing browser | Yes | No, launches new | Partial, needs debug port | | Sessions and cookies | Already there | Fresh profile | Manual setup | | Works behind corporate SSO | Yes | No | Depends | | Setup | Extension + MCP config | Headless browser | Chrome with --remote-debugging-port |


🧠 Teach Your Agent

The agent can use all 18 tools out of the box, but it works better when it knows when and how to chain them. A config file teaches the right workflow - snapshot first, then act, then verify.

Run one command:

npx real-browser-mcp --setup cursor

This installs:

  • ~/.cursor/rules/real-browser-mcp.mdc - teaches the snapshot-first workflow, how to handle dropdowns, when to use screenshots vs snapshots
  • ~/.cursor/commands/check-browser.md - adds /check-browser to your Cursor chat

After that, type /check-browser in any chat. Or just say "check the result in my browser" and the agent knows what to do.

npx real-browser-mcp --setup claude

Adds an AGENTS.md to your project root. Claude Code auto-discovers it.

See agent-config/ for manual installation or to customize the rules.


What It Can Do

18 tools. Grouped by purpose.

See

| Tool | What it does | |------|-------------| | browser_snapshot | Accessibility tree with element refs. Compact mode (default) returns only interactive elements | | browser_screenshot | Capture what's on screen | | browser_text | Extract raw text from page or element | | browser_find | Query elements by CSS selector |

Interact

| Tool | What it does | |------|-------------| | browser_click | Click by ref or CSS selector | | browser_click_text | Click by visible text. Works through React portals and overlays | | browser_type | Type into inputs and contenteditable fields | | browser_press_key | Key combos (Enter, Escape, Ctrl+A) | | browser_scroll | Scroll pages and virtual containers | | browser_hover | Trigger tooltips and dropdowns | | browser_select | Pick from native <select> dropdowns | | browser_wait | Wait for elements to appear or disappear |

Navigate

| Tool | What it does | |------|-------------| | browser_navigate | Go to a URL in the active tab | | browser_tabs | List, create, close, or focus tabs |

Debug

| Tool | What it does | |------|-------------| | browser_console | Console output (log, warn, error) | | browser_network | XHR/fetch requests with status codes | | browser_evaluate | Run JavaScript via Chrome DevTools Protocol | | browser_handle_dialog | Handle alert/confirm/prompt dialogs |


Configuration

| Env var | Default | What it does | |---------|---------|-------------| | WS_PORT | 7225 | WebSocket port for extension connection |

Connection drops are handled automatically with exponential backoff (1s to 30s), ping/pong health checks every 10s, and per-tool timeouts (5s for clicks, 60s for navigation).

Run two server instances on different ports:

{
  "mcpServers": {
    "browser-work": {
      "command": "npx", "args": ["-y", "real-browser-mcp"]
    },
    "browser-personal": {
      "command": "npx", "args": ["-y", "real-browser-mcp"],
      "env": { "WS_PORT": "9333" }
    }
  }
}

Update the port in each extension popup to match.


Everything stays on your machine. The extension connects to the MCP server via WebSocket on localhost. No cloud, no proxy, nothing leaves your browser.

real-browser-mcp/
├── mcp-server/          MCP server (npm package, TypeScript)
│   └── src/tools/       One file per tool, registry pattern
├── extension/           Chrome extension (Manifest V3, plain JS)
│   ├── background.js    Service worker, WebSocket client, tool handlers
│   ├── content.js       Console capture
│   └── popup/           Connection status UI
├── agent-config/        Pre-built configs for Cursor + Claude Code
│   ├── cursor/          Rules and commands
│   ├── skills/          Browser automation skill
│   └── setup.mjs        One-command installer
└── tests/               Bridge + registry tests

Stack: TypeScript (strict) · MCP SDK · WebSocket · Chrome Extension Manifest V3 · Vitest

git clone https://github.com/ofershap/real-browser-mcp.git
cd real-browser-mcp
npm install
npm run build
npm test

| Command | What it does | |---------|-------------| | npm run build | Compile TypeScript | | npm run dev | Watch mode | | npm test | Run tests | | npm run typecheck | Type check without emitting | | npm run setup:cursor | Install Cursor rule + command |

FAQ

That's the whole point. The extension runs inside your actual Chrome - same cookies, same sessions, same local storage. No re-authentication needed.

No. The MCP server and extension talk over WebSocket on localhost. Nothing leaves your machine. There's no analytics, no telemetry, no cloud component. Privacy policy.

Any MCP-compatible client. Cursor, Claude Desktop, Claude Code, Windsurf, Cline, and anything else that speaks the MCP protocol.

Yes. Run two MCP server instances on different ports. See Configuration for the setup.

They launch a new browser instance from scratch - no state, no cookies, no sessions. You have to replay the full login flow every time. This connects to the browser you already have open with everything already loaded.


Contributing

Bug reports, feature requests, and PRs welcome. Open an issue first for larger changes.

Author

Made by ofershap

LinkedIn GitHub


README built with README Builder

License

MIT © Ofer Shapira