MCPBrowser (MCP fetch tool with authenticated Chrome)

Alternative web fetcher for GitHub Copilot when normal URL access fails due to authentication or anti-crawler restrictions. Uses your Chrome/Edge browser session via DevTools to bypass login requirements and bot detection.

🚀 Installation Options

Option 1: VS Code Extension (Easiest - One Click)

From VS Code Marketplace:

code --install-extension cherchyk.mcpbrowser

Or search "MCPBrowser" in VS Code Extensions view.

From GitHub Release: Download from GitHub Releases:

code --install-extension mcpbrowser-0.1.4.vsix

The extension automatically:

• Installs the MCPBrowser npm package globally
• Configures mcp.json for GitHub Copilot
• Complete one-click setup - no manual steps needed

📦 View on Marketplace

Option 2: npm Package (Recommended for Manual Setup)

Published on npm as mcpbrowser v0.2.2.

Add to your mcp.json:

"MCPBrowser": {
  "type": "stdio",
  "command": "npx",
  "args": ["-y", "mcpbrowser@latest"],
  "description": "Loads authenticated web pages using your Chrome session"
}

mcp.json Location:

• Windows: %APPDATA%\Code\User\mcp.json
• Mac/Linux: ~/.config/Code/User/mcp.json

Option 3: MCP Registry

Available in the MCP Registry as io.github.cherchyk/browser v0.2.2.

Search for "browser" in the registry to find configuration instructions.

Option 4: Clone from GitHub (Development)

git clone https://github.com/cherchyk/MCPBrowser.git
cd MCPBrowser
npm install
copy .env.example .env  # optional: set Chrome overrides

Add to mcp.json:

"MCPBrowser": {
  "type": "stdio",
  "command": "node",
  "args": ["<PATH_TO_MCPBROWSER>/src/mcp-browser.js"],
  "description": "Loads authenticated web pages using your Chrome session"
}

Prereqs

• Chrome or Edge installed.
• Node 18+.

Run (automatic via Copilot)

• Add the MCP server entry to VS Code settings (github.copilot.chat.modelContextProtocolServers, see below). Copilot will start the server automatically when it needs the tool—no manual launch required.
• On first use, the server auto-launches Chrome/Edge with remote debugging if it cannot find an existing DevTools endpoint. Defaults: port 9222, user data dir %LOCALAPPDATA%/ChromeAuthProfile. Override with CHROME_PATH, CHROME_USER_DATA_DIR, or CHROME_REMOTE_DEBUG_PORT.
• The old scripts/start-all.ps1 launcher was removed; Chrome startup is handled inside the MCP server.

Manual start (optional)

Only if you want to run it yourself (Copilot already starts it when configured):

npm run mcp

Or manually:

& "C:\Program Files\Google\Chrome\Application\chrome.exe" --remote-debugging-port=9222 --user-data-dir="$env:LOCALAPPDATA\ChromeAuthProfile"

Set CHROME_PATH if auto-detect fails; override profile with CHROME_USER_DATA_DIR, port with CHROME_REMOTE_DEBUG_PORT.

(Optional) Local runner

There is no local LLM runner now; Copilot provides the LLM and calls this MCP tool. If you need a standalone agent later, we can add one that reuses the fetch logic.

How it works

• Tool load_and_extract (inside the MCP server) drives your live Chrome (DevTools Protocol) so it inherits your auth cookies, returning text and html (truncated up to 2M chars per field) for analysis.
• Domain-aware tab reuse: Automatically reuses the same tab for URLs on the same domain, preserving authentication session. Different domains open new tabs.
• Automatic page loading: Waits for network idle (networkidle0) by default, ensuring JavaScript-heavy pages (SPAs, dashboards) fully load before returning content.
• Automatic auth detection: Detects ANY authentication redirect (domain changes, login/auth/sso/oauth URLs) and waits for you to complete sign-in, then returns to target page.
• Universal compatibility: Works with Microsoft, GitHub, AWS, Google, Okta, corporate SSO, or any authenticated site.
• Smart timeouts: 60s default for page load, 10 min for auth redirects. Tabs stay open indefinitely for reuse (no auto-close).
• GitHub Copilot's LLM invokes this tool via MCP; this repo itself does not run an LLM.

Distribution

MCPBrowser is available through three channels:

1. VS Code Extension (easiest): cherchyk.mcpbrowser - One-click configuration
2. npm: mcpbrowser v0.2.2 - Use with npx
3. MCP Registry: io.github.cherchyk/browser v0.2.2 - Discoverable in registry

All three methods configure the same underlying MCP server that drives Chrome via DevTools Protocol.

Auth-assisted fetch flow

• Copilot can call with just the URL, or with no params if you set an env default (DEFAULT_FETCH_URL or MCP_DEFAULT_FETCH_URL). By default tabs stay open indefinitely for reuse (domain-aware).
• First call opens the tab and leaves it open so you can sign in. No extra params needed.
• After you sign in, call the same URL again; tab stays open for reuse. Set keepPageOpen: false to close immediately on success.
• Optional fields (authWaitSelector, waitForSelector, waitForUrlPattern, etc.) are available but not required.

Configuration

• .env: optional overrides for CHROME_WS_ENDPOINT, CHROME_REMOTE_DEBUG_HOST/PORT, CHROME_PATH, CHROME_USER_DATA_DIR.
• To use a specific WS endpoint: set CHROME_WS_ENDPOINT from Chrome chrome://version DevTools JSON.

Tips

• Universal auth: Works with ANY authenticated site (Microsoft, GitHub, AWS, Google, corporate intranets, SSO, OAuth, etc.)
• No re-authentication needed: Automatically reuses the same tab for URLs on the same domain, keeping your auth session alive across multiple page fetches
• Automatic page loading: Tool waits for pages to fully load (default 60s timeout, waits for network idle). Copilot should trust the tool and not retry manually.
• Auth redirect handling: Auto-detects auth redirects by monitoring domain changes and common login URL patterns (/login, /auth, /signin, /sso, /oauth, /saml)
• Tabs stay open: By default tabs remain open indefinitely for reuse. Set keepPageOpen: false to close immediately after successful fetch.
• Smart domain switching: When switching domains, automatically closes the old tab and opens a new one to prevent tab accumulation
• If you hit login pages, verify Chrome instance is signed in and the site opens there.
• Use a dedicated profile directory to avoid interfering with your daily Chrome.
• For heavy pages, add waitForSelector to ensure post-login content appears before extraction.