Browser MCP Server

Browser MCP by Agent360

Control your real Chrome from Claude Code — with your logins, cookies, and 2FA.

The only browser MCP with multi-session support (10 concurrent AI sessions), human-in-the-loop (2FA, CAPTCHA, credentials), and built-in provider integrations (Stripe, HubSpot, Slack, and 6 more). 29 tools total.

Install — 2 steps (~60 seconds)

Step 1: Configure the MCP server

npx @agent360/browser-mcp install

This copies the Chrome extension files to ~/.browser-mcp/extension/ and adds the MCP server to your Claude Code config. You'll see the path to the extension folder printed in the terminal — copy it.

Step 2: Load the extension in Chrome

Chrome won't let extensions install themselves from npm — you have to load it manually one time. After that, it auto-updates whenever you re-run the install command.

1. Open Chrome and type chrome://extensions in the address bar
2. Toggle "Developer mode" ON (top right corner)
3. Click "Load unpacked" (top left, next to "Pack extension")
4. Navigate to ~/.browser-mcp/extension/ and click "Select"
   • On Mac: Press Cmd+Shift+G in the file picker, paste ~/.browser-mcp/extension/, press Enter
   • On Windows: Paste %USERPROFILE%\.browser-mcp\extension\ in the address bar
   • On Linux: Type ~/.browser-mcp/extension/ in the path field
5. Restart Claude Code so it picks up the new MCP server

That's it. The Browser MCP icon will appear in your toolbar, and 29 browser tools are now available in Claude Code.

Alternative: Manual zip download (no npm)

If you don't want to use npm, download the extension directly:

1. Download browser-mcp-v1.16.1.zip from the latest GitHub release
2. Unzip the file (anywhere — e.g. ~/Downloads/browser-mcp-extension/)
3. Follow Step 2 above, but select the unzipped folder instead of ~/.browser-mcp/extension/
4. Configure Claude Code manually by adding this to your ~/.claude.json (or run npx @agent360/browser-mcp install --skip-extension):

   {
     "mcpServers": {
       "browser-mcp": {
         "command": "npx",
         "args": ["@agent360/browser-mcp"]
       }
     }
   }
   

Chrome Web Store (one-click install)

Install from Chrome Web Store →

No Developer mode needed. Then run npx @agent360/browser-mcp install --skip-extension to configure Claude Code.

Why This Over Playwright MCP / BrowserMCP?

29 Tools

Navigation & Content

Interaction

Tabs & Frames

Data & Network

CAPTCHA Solving

Human-in-the-Loop

Data

Multi-Session Support

Each Claude Code conversation gets its own MCP server on a unique port (9876-9885). The Chrome extension connects to all active servers simultaneously.

Claude Session 1 ←(stdio)→ MCP :9876 ←(WS)→
Claude Session 2 ←(stdio)→ MCP :9877 ←(WS)→  Chrome Extension → Browser
Claude Session 3 ←(stdio)→ MCP :9878 ←(WS)→

• Session isolation — each session gets a color-coded Chrome Tab Group
• Tab ownership — sessions can only see and control their own tabs
• Auto-cleanup — processes exit when Claude Code closes the conversation

Built-in Provider Integrations

browser_extract_token navigates to the provider's API settings page and guides token extraction:

Architecture

extension/
  manifest.json       # Manifest V3
  background.js       # Service worker — Chrome API dispatcher, session tab groups
  offscreen.js        # Persistent WebSocket bridge (multi-port scanning)
  popup.html/js       # Status UI — sessions, tabs, action log

mcp-server/
  index.js            # MCP server (stdio) + WebSocket client
  tools.js            # 29 tool definitions
  bin/cli.js          # Install CLI

How It Works

1. Claude Code starts → spawns MCP server via stdio
2. MCP server binds to first available port (9876-9885)
3. Extension's offscreen document scans ports every 2s
4. WebSocket connection established
5. Commands flow: Claude Code → MCP → Extension → Chrome APIs
6. Process auto-exits when Claude Code closes (stdin detection)

Auto-Updates

The MCP server runs via npx @agent360/browser-mcp@latest — always the latest version from npm. No manual git pulls needed.

To update the extension: npx @agent360/browser-mcp install (re-copies files), then reload in chrome://extensions.

Troubleshooting

"Chrome extension not connected"

• Check extension is loaded in chrome://extensions
• Click the extension popup → "Reconnect"
• Wait 2-3 seconds for port scan

Screenshot fails

• Uses Chrome Debugger API (works even when tab isn't focused)
• Falls back to captureVisibleTab if debugger unavailable

Click doesn't work on SPA

• Try text selector: browser_click("text=Submit")
• Uses real mouse events via Chrome Debugger API automatically

Stale processes

• Processes auto-exit when Claude Code closes (stdin detection)
• Idle timeout: 4 hours without commands → auto-exit
• Manual cleanup: lsof -i :9876-9885 | grep LISTEN

License

MIT — Agent360