chrome-ai-bridge


> ⚠️ Requires Chrome Extension — This MCP server 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 → MCP Server → Chrome Extension → ChatGPT/Gemini tabs
`

1. Chrome Extension (you install) bridges MCP server and browser
2. MCP Server (npm package) receives requests from your AI assistant
3. Extension controls ChatGPT/Gemini tabs via CDP (Chrome DevTools Protocol)

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

---

What is this?

chrome-ai-bridge is a Model Context Protocol server 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.

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| | 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) |

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`
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 MCP server work together.

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Build and install the extension from this repository:

`bash


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.

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For Claude Code (~/.claude.json):

`json
{
"mcpServers": {
"chrome-ai-bridge": {
"command": "npx",
"args": ["chrome-ai-bridge@latest"]
}
}
}
`

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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 MCP server starts

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Restart your AI client and try: "Ask ChatGPT how to implement OAuth in Node.js"

---

Features

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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 |

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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

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| 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 |

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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

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

---

For Developers

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

Configure ~/.claude.json to use local build:

`json
{
"mcpServers": {
"chrome-ai-bridge": {
"command": "node",
"args": ["/path/to/chrome-ai-bridge/scripts/cli.mjs"]
}
}
}
`

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

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

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`bash


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 MCP configuration |
| Troubleshooting | Problem solving |
| Technical Spec - Architecture | Extension architecture |

---

Troubleshooting

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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

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`bash
npx clear-npx-cache && npx chrome-ai-bridge@latest
`

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- 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)

`
┌─────────────────┐ MCP ┌──────────────────┐
│ Claude Code │ ◀──────────────────▶│ MCP Server │
│ (MCP Client) │ │ (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