React Native AI DevTools

An MCP server that gives AI assistants real-time access to a running React Native app. It bridges the gap between static code and live runtime, turning AI assistants from guessing machines into informed development partners.

Positioning: This is not a debugger. This is not a QA tool. This is a Runtime AI Bridge — the missing layer between AI coding assistants and live mobile applications. Without it, your AI assistant is blind. With it, the AI sees everything happening in your app in real time.

Feedback & Feature Requests

Have an idea or found something that could be better? Head over to GitHub Discussions to share feedback, request features, and vote on what gets built next.

Features

Runtime Interaction

• Console Log Capture - Capture console.log, warn, error, info, debug with filtering and search. Note: on a cold start (first app launch), logs emitted before the MCP server connects are missed — subsequent reloads capture everything. Install the optional SDK to buffer logs from the very first line of app startup

• Network Request Tracking - Monitor HTTP requests/responses with headers, timing, and body content. Like logs, early network requests on cold start may be missed before the connection is established. Install the optional SDK for full capture from app startup including request/response bodies

• JavaScript Execution - Run code directly in your app (REPL-style) and inspect results

• Global State Debugging - Discover and inspect Apollo Client, Redux stores, Expo Router, and custom globals

• Bundle Error Detection - Get Metro bundler errors and compilation issues with file locations

Device Control

• iOS Simulator - Screenshots, app management, URL handling, boot/terminate (via simctl)

• Android Devices - Screenshots, app install/launch, package management (via ADB)

• Unified Tap - Single tap tool with automatic fallback chain: fiber tree → accessibility → OCR → coordinates. Auto-detects platform, accepts pixels from screenshots. Returns post-tap screenshot and verifies visual change by default

• UI Automation - Swipe, long press, text input, and key events on both platforms

• Accessibility Inspection - Query UI hierarchy to find elements by text, label, or resource ID

• OCR Text Extraction - Extract visible text with tap-ready coordinates via Google Cloud Vision (works on any screen content)

Multi-Device Debugging

• Connect All Devices - scan_metro automatically discovers and connects to all Bridgeless targets on each Metro port

• Device Targeting - Every tool accepts an optional device parameter for targeting specific devices by name (case-insensitive substring match)

• Per-Device Buffers - Logs and network requests are captured separately per device for clean debugging

• Cross-Platform Comparison - Debug iOS and Android side-by-side, comparing logs, network traffic, and component trees

Under the Hood

• Auto-Discovery - Scans Metro on ports 8081, 8082, 19000-19002 automatically

• Multi-Device Support - Connects to all Bridgeless targets simultaneously, with per-device log and network buffers

• Auto-Reconnection - Exponential backoff (up to 8 attempts) when connection drops

• Efficient Buffering - Circular buffers: 500 logs, 200 network requests

• Platform Support - Expo SDK 54+ (Bridgeless) and React Native 0.70+ (Hermes)

Platform Setup

Android

Android works out of the box — all device control tools use ADB, which ships with Android Studio. Verify it's available:

adb devices

iOS Simulator — UI Automation Setup

iOS UI automation tools (tap, swipe, text input, accessibility queries) require a UI driver. Install one of the following:

Option A: AXe CLI (experimental)

AXe is a standalone CLI for iOS simulator automation. No daemon required — single binary, simple setup.

brew install cameroncooke/axe/axe

Verify: axe --version

Add env to your MCP server configuration:

{
  "mcpServers": {
    "rn-debugger": {
      "type": "stdio",
      "command": "npx",
      "args": ["react-native-ai-devtools"],
      "env": { "IOS_DRIVER": "axe" }
    }
  }
}

Note: AXe text input only supports US keyboard layout characters.

Option B: IDB

IDB (iOS Development Bridge) is a tool built by Meta for automating iOS Simulators. Requires a background daemon.

brew install idb-companion

Verify: idb_companion --list 1

IDB is the default driver — no IOS_DRIVER env var needed.

What works without a UI driver:

Troubleshooting: If you see errors like "IDB is not installed" or "AXe is not installed" in tap results, install the appropriate driver with the commands above and retry.

Requirements

• Node.js 18+

• React Native app running with Metro bundler

• iOS UI automation: Facebook IDB (brew install idb-companion) or AXe CLI (brew install cameroncooke/axe/axe) — required for tap, swipe, text input, accessibility on iOS Simulator

• Optional for offline OCR fallback: Python 3.6+ (only needed when cloud OCR is unavailable, see OCR Setup)

Claude Code Setup

No installation required - Claude Code uses npx to run the latest version automatically.

Global (all projects)

claude mcp add rn-debugger --scope user -- npx react-native-ai-devtools

Project-specific

claude mcp add rn-debugger --scope project -- npx react-native-ai-devtools

Manual Configuration

Add to ~/.claude.json (user scope) or .mcp.json (project scope):

{
  "mcpServers": {
    "rn-debugger": {
      "type": "stdio",
      "command": "npx",
      "args": ["react-native-ai-devtools"]
    }
  }
}

Restart Claude Code after adding the configuration.

VS Code Copilot Setup

Requires VS Code 1.102+ with Copilot (docs).

Via Command Palette: Cmd+Shift+P → "MCP: Add Server"

Manual config - add to .vscode/mcp.json:

{
  "servers": {
    "rn-debugger": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "react-native-ai-devtools"]
    }
  }
}

Cursor Setup

Docs

Via Command Palette: Cmd+Shift+P → "View: Open MCP Settings"

Manual config - add to .cursor/mcp.json (project) or ~/.cursor/mcp.json (global):

{
  "mcpServers": {
    "rn-debugger": {
      "command": "npx",
      "args": ["-y", "react-native-ai-devtools"]
    }
  }
}

Claude Code Skills

Pre-built skills for common debugging workflows — session setup, log inspection, network debugging, and more. See the skills guide for the full list and installation instructions.

Available Tools

See the full tool reference for all tools with descriptions. Key tools:

Usage

1. Start your React Native app:

   npm start
   # or
   expo start

2. In Claude Code, scan for Metro:

   Use scan_metro to find and connect to Metro

3. Get logs:

   Use get_logs to see recent console output

Detailed Guides

Supported React Native Versions

How It Works

1. Fetches device list from Metro's /json endpoint

2. Connects to the main JS runtime via CDP (Chrome DevTools Protocol) WebSocket

3. Enables Runtime.enable to receive Runtime.consoleAPICalled events

4. Network capture via two paths:

   • With SDK: Reads from the SDK's in-app buffer via Runtime.evaluate — captures all requests from startup with full headers and bodies, including cold-start events that CDP would miss

   • Without SDK: Enables CDP Network.enable (on supported targets) or injects a JS fetch interceptor as fallback. On cold start, events emitted before the CDP connection is established are lost; subsequent reloads capture everything

5. Stores logs and network requests in circular buffers for retrieval

Connection Management

Explicit Connection

The server does not auto-connect on startup. Call scan_metro to discover and connect to Metro servers. This prevents multiple MCP server instances (from parallel agent sessions) from competing for the single CDP WebSocket slot, which would cause connection thrashing and dropped tools.

Graceful Shutdown

When the MCP server process is terminated (SIGINT/SIGTERM), it closes all CDP WebSocket connections and cancels reconnection timers, freeing the CDP slot immediately for other sessions.

Reconnection on Disconnect

When the connection to Metro is lost (e.g., app restart, Metro restart, or network issues):

1. The server automatically attempts to reconnect

2. Uses exponential backoff: 500ms, 1s, 2s, 4s, 8s (up to 8 attempts)

3. Re-fetches device list to handle new WebSocket URLs

4. Preserves existing log and network buffers

Connection Gap Warnings

If there was a recent disconnect, get_logs and get_network_requests will include a warning:

[WARNING] Connection was restored 5s ago. Some logs may have been missed during the 3s gap.

Monitor Connection Health

Use get_connection_status to see detailed connection information:

=== Connection Status ===

--- React Native (Port 8081) ---
  Status: CONNECTED
  Connected since: 2:45:30 PM
  Uptime: 5m 23s
  Recent gaps: 1
    - 2:43:15 PM (2s): Connection closed

Troubleshooting

No devices found

• Make sure the app is running on a simulator/device

• Check that Metro bundler is running (npm start)

Wrong device connected

The server prioritizes devices in this order:

1. React Native Bridgeless (SDK 54+)

2. Hermes React Native

3. Any React Native (excluding Reanimated/Experimental)

Logs not appearing

• Ensure the app is actively running (not just Metro)

• Try clear_logs then trigger some actions in the app

• Check get_apps to verify connection status

• On cold start (first launch): The CDP connection is established after the app's early initialization code has already run, so startup logs and network requests are missed. Once connected, use reload_app — the subsequent reload captures everything from the beginning because the connection is already in place. To capture startup events on every launch, install the optional SDK

Telemetry & Data Collection

This package collects anonymous usage telemetry to help improve the product. No personal information is collected.

What is collected

Not collected: No file paths, code content, network data, or personally identifiable information.

Auto-registration

On first tool use, the package automatically registers your installation with our backend. No account or login is required — the Tool works fully out of the box.

Why we do this: The product roadmap includes features that build on installation identity — project memory (your AI assistant gets smarter with every session by remembering navigation maps, element signatures, and debug patterns), cloud sync across machines, team collaboration with shared debugging context, and a Pro dashboard for managing installations and subscriptions. Auto-registration lays the groundwork so these features work seamlessly when they ship, without requiring a disruptive setup step later.

What is sent:

• A random installation ID (UUID)

• A device fingerprint (one-way SHA-256 hash — cannot be reversed to recover its components)

• Platform, hostname, OS version, and server version

What is NOT sent: No source code, file paths, console logs, network data, component names, or any content from your app. The fingerprint exists solely to prevent installation hijacking — it ties your installation to your physical machine so no one else can claim it.

Registration is fire-and-forget — it never blocks your work, fails silently if the network is unavailable, and can be disabled entirely (see Opt-out below). See PRIVACY.md for full details on data handling, storage, and your rights.

Opt-out

To disable telemetry and auto-registration, add RN_DEBUGGER_TELEMETRY to the env field in your MCP server configuration:

{
  "mcpServers": {
    "rn-debugger": {
      "type": "stdio",
      "command": "npx",
      "args": ["react-native-ai-devtools"],
      "env": { "RN_DEBUGGER_TELEMETRY": "false" }
    }
  }
}

All debugging tools work normally with telemetry disabled. For the complete privacy policy, see PRIVACY.md.

License

MIT