Open Claude in Chrome

Claude in Chrome, fully open source. No domain blocklist. Any Chromium browser.

The official Claude in Chrome extension gives Claude Code full browser automation. Open Claude in Chrome is a clean-room reimplementation that removes the restrictions while maintaining 100% feature and performance parity.

Demo: Watch Claude on Tinder, Reddit, and Robinhood | Deep dive: How I reverse-engineered it

What's Different

| | Claude in Chrome | Open Claude in Chrome | |---|---|---| | Domain blocklist | 58 blocked domains across 11 categories | No blocklist. Navigate anywhere. | | Browser support | Chrome and Edge only | Any Chromium browser (Chrome, Edge, Brave, Arc, Opera, Vivaldi, etc.) | | Source code | Closed source | Open source (MIT) | | Tools | 18 MCP tools | Same 18 MCP tools | | Performance | Baseline | Identical |

Blocked Domains in the Official Extension

| Category | Blocked Sites | |----------|--------------| | Banking | Chase, BofA, Wells Fargo, Citibank | | Investing/Brokerage | Schwab, Fidelity, Robinhood, E-Trade, Wealthfront, Betterment | | Payments/Transfers | PayPal, Venmo, Cash App, Zelle, Stripe, Square, Wise, Western Union, MoneyGram, Adyen, Checkout.com | | BNPL | Klarna, Affirm, Afterpay | | Neobanks/Fintech | SoFi, Chime, Mercury, Brex, Ramp | | Crypto | Coinbase, Binance, Kraken, MetaMask | | Gambling | DraftKings, FanDuel, Bet365, Bovada, PokerStars, BetMGM, Caesars | | Dating | Tinder, Bumble, Hinge, Match, OKCupid | | Adult | Pornhub, XVideos, XNXX | | News/Media | NYT, WSJ, Barron's, MarketWatch, Bloomberg, Reuters, Economist, Wired, Vogue | | Social Media | Reddit |

Open Claude in Chrome has none of these restrictions.

Architecture

Claude Code <--stdio MCP--> mcp-server.js <--TCP--> native-host.js <--native messaging--> Extension <--> Browser

Three components:

1. Extension — Manifest V3 with CDP-based browser automation (all 18 tools)
2. MCP Server — Node.js process started by Claude Code, exposes tools via MCP
3. Native Messaging Host — Bridge between the MCP server and the extension

Installation

Prerequisites

• Node.js v18+
• Any Chromium browser (Chrome, Edge, Brave, Arc, Opera, Vivaldi, etc.)
• Claude Code v2.0.73+

Step 1: Install dependencies

cd host
npm install
cd ..

Step 2: Load the extension

1. Go to chrome://extensions (or brave://extensions / edge://extensions)
2. Enable Developer mode
3. Click Load unpacked and select the extension/ directory
4. Copy the extension ID shown under the extension name

Step 3: Register native messaging

./install.sh <your-extension-id>

If you use multiple browsers, pass all IDs:

./install.sh <chrome-id> <brave-id> <arc-id>

Step 4: Restart your browser

Close all windows and reopen. The browser reads native messaging host configs on startup.

Step 5: Add to Claude Code

claude mcp add open-claude-in-chrome -- node /absolute/path/to/host/mcp-server.js

Find the absolute path with:

echo "node $(pwd)/host/mcp-server.js"

Verification

Start a new Claude Code session and test:

Navigate to reddit.com and take a screenshot

Reddit loads. No domain restriction.

Available Tools

All 18 tools, identical to Claude in Chrome:

| Tool | Description | |------|-------------| | tabs_context_mcp | Get tab group context | | tabs_create_mcp | Create new tab | | navigate | Navigate to URL, back, forward | | computer | Mouse, keyboard, screenshots (13 actions) | | read_page | Accessibility tree with element refs | | get_page_text | Extract article/main text | | find | Find elements by text/at

... View full README on GitHub