replicant-mcp

replicant-mcp

Let AI build, test, and debug your Android apps.

replicant-mcp is a Model Context Protocol server that gives AI assistants like Claude the ability to interact with your Android development environment. Build APKs, launch emulators, install apps, navigate UIs, and debug crashes—all through natural conversation.

Demo

Why replicant-mcp?

Features

Coming Soon

• Custom build commands (project-specific overrides, auto-detect gradlew)
• Video capture (start/stop recording, duration-based capture)

Quick Start

Prerequisites

• Node.js 18+
• Android SDK with adb and emulator in your PATH
• An Android project with gradlew (for build tools)

node --version      # Should be 18+
adb --version       # Should show Android Debug Bridge version
emulator -version   # Should show Android emulator version

Installing prerequisites (macOS via Homebrew)

If you don't already have these tools, install them with Homebrew:

Node.js 18+

brew install node

Physical-device only — just adb, sufficient if you never run an emulator:

brew install --cask android-platform-tools

adb lands directly on your PATH; no further config needed.

Full Android SDK — needed for emulator workflows or building APKs via the gradle-* tools. Run the steps in order:

# 1. JDK — required by sdkmanager itself, and by the gradle-* tools
brew install --cask temurin@17

# 2. cmdline-tools (provides sdkmanager)
brew install --cask android-commandlinetools

# 3. Set ANDROID_HOME and create the directory BEFORE running sdkmanager,
#    otherwise sdkmanager has no install target.
export ANDROID_HOME="$HOME/Library/Android/sdk"
mkdir -p "$ANDROID_HOME"

# 4. Accept all SDK licenses first, then install packages.
#    `sdkmanager --install` aborts on unaccepted per-package licenses
#    (e.g. the Google APIs system image) if licenses aren't accepted first.
#    The system-image arch must match your host: `arm64-v8a` for Apple
#    Silicon (M1/M2/M3), `x86_64` for Intel Macs. Check with `uname -m`.
yes | sdkmanager --licenses
sdkmanager --install "platform-tools" "emulator" "system-images;android-34;google_apis;arm64-v8a"

Persist ANDROID_HOME and put the SDK binaries on your PATH by appending to ~/.zshrc (or ~/.bashrc):

export ANDROID_HOME="$HOME/Library/Android/sdk"
export PATH="$ANDROID_HOME/platform-tools:$ANDROID_HOME/emulator:$PATH"

Installation

npm install -g replicant-mcp

After installation, run the built-in diagnostics to verify your environment:

replicant doctor

Updating

npm update -g replicant-mcp

Setup

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "replicant": {
      "command": "npx",
      "args": ["-y", "replicant-mcp"]
    }
  }
}

Claude Code

claude mcp add replicant -- npx -y replicant-mcp

Cursor

Add to ~/.cursor/mcp.json (global) or .cursor/mcp.json (project):

{
  "mcpServers": {
    "replicant": {
      "command": "npx",
      "args": ["-y", "replicant-mcp"]
    }
  }
}

Windsurf

Add to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "replicant": {
      "command": "npx",
      "args": ["-y", "replicant-mcp"]
    }
  }
}

OpenAI Codex CLI

Add to ~/.codex/config.toml:

[mcp_servers.replicant]
command = "npx"
args = ["-y", "replicant-mcp"]

Or via CLI:

codex mcp add replicant -- npx -y replicant-mcp

Note: Ensure adb and emulator are in your PATH, or set ANDROID_HOME environment variable. On macOS: ~/Library/Android/sdk, on Linux: ~/Android/Sdk.

Example

You: "I just changed the checkout flow. Build the app, go through checkout
      with a test product, and make sure the confirmation screen shows up."

Claude: [Builds debug APK, installs on emulator, launches app]
        [Taps "Electronics" category → "Wireless Headphones" → "Add to Cart"]
        [Navigates to cart, taps "Checkout"]
        [Fills shipping form, taps "Place Order"]

        Confirmation screen is showing:
        - Order #38291
        - "Wireless Headphones" × 1
        - Total: $79.99
        - Estimated delivery: Jan 30

        The flow works. Want me to test the edge cases—empty cart,
        invalid address, payment failure?

Design

replicant-mcp uses progressive disclosure (summaries first, details on demand) to minimize token usage, and accessibility-first UI automation for faster, cheaper, more reliable interactions than screenshot-based approaches. See docs/architecture.md for details.

More Info

• Configuration: Set REPLICANT_CONFIG for advanced options. See docs/configuration.md.
• Logging: Set REPLICANT_LOG_LEVEL (error, warn, info, debug) and REPLICANT_LOG_FORMAT (json for structured output) to control server logging. Logs are written to stderr.
• Troubleshooting: Common issues and solutions in docs/troubleshooting.md.
• Tool documentation: Ask Claude to call rtfm with a category like "build", "adb", "emulator", or "ui".

Documentation

Contributing

See CONTRIBUTING.md for development setup and guidelines.

Acknowledgments

• Inspired by xc-mcp for iOS
• Built on the Model Context Protocol

License

MIT

Questions? Open an issue