chrome-ai-bridge

Requires Chrome Extension — This CLI tool controls ChatGPT/Gemini tabs via a browser extension.

Let your AI assistant (Claude Code, Cursor, etc.) consult ChatGPT and Gemini for second opinions.

How it works

Your AI Assistant → cab CLI / daemon → Chrome Extension → ChatGPT/Gemini tabs

1. Chrome Extension (you install) bridges the daemon and browser
2. cab CLI / daemon (npm package) receives requests from your AI assistant via REST API
3. Extension controls ChatGPT/Gemini tabs via CDP (Chrome DevTools Protocol)

Why an extension? ChatGPT and Gemini don't have free public APIs. The extension automates the web UI while you stay logged in.

What is this?

chrome-ai-bridge is a CLI tool and daemon that gives AI assistants the ability to:

• Consult other AIs: Ask ChatGPT and Gemini questions via browser
• Get multiple perspectives: Query both AIs in parallel for second opinions
• Debug connections: Inspect page state via CDP snapshots

v2.0.0 Breaking Change: This version uses a Chrome extension for browser communication instead of Puppeteer. Previous CLI options (--headless, --loadExtensionsDir, etc.) are no longer supported.

What's New in v2.1 — Network-Native Stream

UI changes? No problem. Responses won't break anymore.

v2.1 introduces a fundamentally new approach to response extraction. Instead of reading text from the page (DOM), chrome-ai-bridge now intercepts the actual network communication between your browser and ChatGPT/Gemini.

Before vs After

| | v2.0 (DOM extraction) | v2.1 (Network interception) | |---|---|---| | How it works | Read HTML elements via CSS selectors | Intercept API responses directly | | When UI changes | Breaks (selectors become invalid) | Unaffected | | Output format | Plain text only | Markdown, LaTeX, structured content | | Thinking mode | Complex filtering needed | Naturally separated by protocol | | Reliability | Depends on page rendering | Depends on API protocol (stable) |

Architecture

v2.0:  CDP → DOM querySelector → innerText
v2.1:  CDP → Network.loadingFinished → getResponseBody → Protocol Parser
                                                              │
                                          ┌───────────────────┴────────────────┐
                                          ▼                                    ▼
                                ChatGPT SSE Parser              Gemini Chunked Parser
                              (delta_encoding v1)             (StreamGenerate format)

Network extraction is the primary path. DOM extraction remains as an automatic fallback — no configuration needed.

Privacy: All data stays local. Network interception happens within your browser via CDP. No data is sent to external servers.

Quick Start

Both steps are required — The extension and daemon work together.

Step 1: Install Chrome Extension

Build and install the extension from this repository:

# Clone the repository
git clone https://github.com/usedhonda/chrome-ai-bridge.git
cd chrome-ai-bridge

# Install dependencies and build
npm install && npm run build

Then load the extension in Chrome:

1. Open chrome://extensions/ in Chrome
2. Enable "Developer mode" (toggle in top-right)
3. Click "Load unpacked"
4. Select the build/extension/ folder from this repository

You should see "Chrome AI Bridge" appear in your extensions list.

Step 2: Install the cab CLI

npm install -g chrome-ai-bridge

Step 3: Connect the Extension

1. Open ChatGPT (https://chatgpt.com) or Gemini (https://gemini.google.com) in Chrome
2. Log in to both services
3. The extension will automatically connect when the daemon starts

Step 4: Verify it works

cab ask chatgpt "How do I implement OAuth in Node.js?"

Features

Multi-AI Consultation

Ask ChatGPT or Gemini questions directly from your AI assistant:

"Ask ChatGPT how to implement OAuth in Node.js"
"Ask Gemini to review this architecture decision"
"Ask both AIs for their opinions on this approach"

| Feature | Description | |---------|-------------| | Parallel queries | Ask both AIs simultaneously with ask_chatgpt_gemini_web | | Session persistence | Conversations continue across tool calls | | Auto-logging | All Q&A saved to .local/chrome-ai-bridge/history.jsonl |

Debugging Tools

Inspect the connection state and page content:

| Tool | Description | |------|-------------| | take_cdp_snapshot | Get page state (URL, title, input/button status) | | get_page_dom | Query DOM elements with CSS selectors |

Tools Reference

Available Tools (5)

| Tool | Description | |------|-------------| | ask_chatgpt_web | Ask ChatGPT via browser | | ask_gemini_web | Ask Gemini via browser | | ask_chatgpt_gemini_web | Ask both AIs in parallel (recommended) | | take_cdp_snapshot | Debug: Get CDP page state | | get_page_dom | Debug: Query DOM elements |

Recommended Usage

For general queries, use ask_chatgpt_gemini_web to get multiple perspectives:

User: "Ask AI about React best practices"
→ Claude uses ask_chatgpt_gemini_web (queries both in parallel)

Only use individual tools when explicitly requested:

User: "Ask ChatGPT specifically about this"
→ Claude uses ask_chatgpt_web

Configuration

Environment Variables

| Variable | Description | |----------|-------------| | CAI_DISABLE_WEB_LLM | Set true to disable ChatGPT/Gemini tools |

For Developers

Local Development

git clone https://github.com/usedhonda/chrome-ai-bridge.git
cd chrome-ai-bridge
npm install && npm run build

For local development, run the daemon directly:

node /path/to/chrome-ai-bridge/scripts/cli.mjs

Commands

npm run build      # Build TypeScript
npm run typecheck  # Type check only
npm run test:smoke # Basic operation check
npm run format     # Format code

Project Structure

chrome-ai-bridge/
├── src/
│   ├── fast-cdp/        # CDP client and AI chat logic
│   ├── extension/       # Chrome extension source
│   ├── main.ts          # Daemon entry point
│   └── index.ts         # Main exports
├── scripts/
│   └── cli.mjs          # CLI entry point
└── docs/                # Documentation

Testing

# Test ChatGPT connection
npm run test:chatgpt -- "TypeScript generics explanation"

# Test Gemini connection
npm run test:gemini -- "Python async file reading"

# Test both
npm run test:both

# CDP snapshot for debugging
npm run cdp:chatgpt
npm run cdp:gemini

Documentation

| Guide | Description | |-------|-------------| | Technical Spec | Detailed architecture and implementation | | Setup Guide | Detailed setup and configuration | | Troubleshooting | Problem solving | | CI Policy | Required checks and browser E2E lane policy | | Technical Spec - Architecture | Extension architecture |

Troubleshooting

Extension not connecting

1. Check that the extension is installed and enabled in chrome://extensions/
2. Verify ChatGPT/Gemini tabs are open and logged in
3. Check the extension popup for connection status

Daemon not responding

cab status
# or restart:
cab daemon restart

ChatGPT/Gemini not responding

• Ensure you're logged in to both services
• Try refreshing the ChatGPT/Gemini tab
• Check for rate limiting or service issues

More: docs/user/troubleshooting.md

Architecture (v2.0.0)

┌─────────────────┐       REST API      ┌──────────────────┐
│  Claude Code    │ ◀──────────────────▶│  Chrome AI Bridge│
│  (cab CLI)      │                     │  (Node.js)       │
└─────────────────┘                     └────────┬─────────┘
                                                 │
                                                 ▼
                                      ┌──────────────────┐
                                      │ Chrome Extension │
                                      │ (CDP via WebSocket)│
                                      └────────┬─────────┘
                                               │
                               ┌───────────────┴───────────────┐
                               ▼                               ▼
                    ┌─────────────────┐             ┌─────────────────┐
                    │  ChatGPT Tab    │             │  Gemini Tab     │
                    └─────────────────┘             └─────────────────┘

Credits

Originally forked from Chrome DevTools MCP by Google LLC. This fork focuses on multi-AI consultation capabilities via Chrome extension.

The extension source code is located at src/extension/ and is built to build/extension/.

License

Apache-2.0