React Native MCP Server

한국어 문서 | Documentation Site

MCP(Model Context Protocol) server for React Native app automation and monitoring. Works with Cursor, Claude Desktop, Claude Code, GitHub Copilot, Windsurf, and any MCP-compatible client.

What makes this different

• React Fiber tree access — Query and inspect components via the actual Fiber tree, not screenshots or accessibility labels
• State inspection — Read React hooks (useState, Zustand, etc.) of any component in real time
• Render profiling — Track mounts, re-renders, and unnecessary renders without React DevTools
• Network mocking — Intercept XHR/fetch and inject mock responses at runtime
• 48 MCP tools — Tap, swipe, screenshot, assert, eval, clear(target), and more across 12 categories
• Zero native module — Pure JS runtime + host CLI tools (adb/idb). No linking, no native code
• YAML E2E testing — Write scenarios in YAML and run in CI without AI

Documentation

Guide	Description
Quick Start	5-minute setup guide
Expo Guide	Expo-specific setup (Dev Client, Expo Go, Expo Router)
Tool Reference	All 49 tools with parameters and examples
Cookbook	Real-world usage scenarios
Architecture	How it works under the hood
Troubleshooting	Connection issues and fixes
VS Code Extension	DevTools + Component Tree in the sidebar
E2E Testing	YAML scenario testing

Quick Start (CLI init)

The fastest way to set up React Native MCP in your project:

npx -y @ohah/react-native-mcp-server init

What it does

The init command runs through these steps:

Step 1 — Project Detection (automatic)

Reads package.json, lock files, and config files to detect:

• React Native version (dependencies.react-native)
• Expo (dependencies.expo, app.json, app.config.ts)
• Babel config location (babel.config.js, .babelrc, etc.)
• Package manager (bun.lock → bun, yarn.lock → yarn, pnpm-lock.yaml → pnpm, otherwise npm)

 Detecting project...
  ✓ React Native 0.83.1
  ✓ Expo detected (expo@~52.0.0)
  ✓ Package manager: bun

Step 2 — MCP Client Selection (interactive prompt)

Asks which MCP client you use. This determines where the server config file is created.

? Which MCP client do you use?
  1. Cursor
  2. Claude Code (CLI)
  3. Claude Desktop
  4. Windsurf
  5. Antigravity
> 1

Client	Config location
Cursor	{project}/.cursor/mcp.json
Claude Code	claude mcp add CLI command
Claude Desktop	~/Library/Application Support/Claude/claude_desktop_config.json (macOS)
Windsurf	~/.codeium/windsurf/mcp_config.json
Antigravity	~/.gemini/antigravity/mcp_config.json

Step 3 — Apply Changes (automatic)

1. babel.config.js — Appends @ohah/react-native-mcp-server/babel-preset to the presets array. Skipped if already present.
2. MCP config — Creates or merges the server entry into the client config file. Existing settings are preserved.
3. .gitignore — Appends /results/ if not already present.

Step 4 — Run your app and start using MCP tools

# Bare RN
npx react-native start

# Expo
npx expo start

Options

# Non-interactive mode — skip prompts, use Cursor as default client
npx -y @ohah/react-native-mcp-server init -y

# Specify client explicitly
npx -y @ohah/react-native-mcp-server init --client cursor
npx -y @ohah/react-native-mcp-server init --client claude-code

# Help
npx -y @ohah/react-native-mcp-server init --help

Running init multiple times is safe — each step checks if the change is already applied.

Usage

Cursor

Add to .cursor/mcp.json:

{
  "mcpServers": {
    "react-native-mcp": {
      "command": "npx",
      "args": ["-y", "@ohah/react-native-mcp-server"]
    }
  }
}

Claude Desktop / Claude Code

# Claude Code CLI (recommended)
claude mcp add --transport stdio react-native-mcp -- npx -y @ohah/react-native-mcp-server

Or edit ~/Library/Application Support/Claude/claude_desktop_config.json with the same JSON structure.

GitHub Copilot CLI

Run /mcp add react-native-mcp in Copilot CLI, or edit ~/.copilot/mcp-config.json.

VS Code Extension (DevTools)

Install React Native MCP DevTools from the Marketplace, or in VS Code: Ctrl+Shift+X (Extensions) → search React Native MCP DevTools → Install. Gives you Console, Network, State, Renders, and Component Tree in the sidebar. See VS Code Extension for local .vsix install.

For detailed client setup, see Cursor / Claude / Copilot.

Required: Native Tools (idb / adb)

The MCP server uses idb (iOS) and adb (Android) for native touch injection and screenshots.

# Android
brew install --cask android-platform-tools  # or install Android Studio
adb devices  # verify

# iOS Simulator
brew tap facebook/fb && brew install idb-companion
pip3 install fb-idb
idb list-targets  # verify

idb is macOS-only, simulators only. See idb Setup Guide for details.

Architecture

React Native App (iOS/Android)
  ↓ (WebSocket)
  └─ Runtime (auto-injected via Babel preset)
       ↓
     MCP Server (developer's machine, port 12300)
       ↓ (stdio/MCP protocol)
     Cursor / Claude Desktop / Copilot CLI

See Architecture for the full design.

Development

• Tools: mise (see .mise.toml), oxlint/oxfmt for linting/formatting
• Scripts:
  • bun run build - Build the server
  • bun run mcp - Run MCP server
  • bun run dev - Watch mode
  • bun run test - Run tests
  • bun run test:mcp - Spawn server, call evaluate_script via stdio

License

MIT © ohah