AndroidBuilder MCP Server

An official Model Context Protocol (MCP) server that connects to running instances of MIT App Inventor, AndroidBuilder, Kodular, or Niotron, allowing LLMs to interact with the Designer and Blocks workspace in real-time via the Chrome DevTools Protocol.

Features

Related MCP server: Chrome DevTools MCP

Prerequisites

1. Node.js ≥ 18

2. Google Chrome / Chromium launched with remote debugging enabled

Setup

1. Launch Chrome with Debugging Port

Windows (PowerShell / CMD):

chrome.exe --remote-debugging-port=9222

macOS:

/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --remote-debugging-port=9222

Open your IDE (androidbuilder.in, App Inventor, etc.) and load your project.

2. Configure MCP Client

Add this server to your MCP client configuration (e.g. claude_desktop_config.json):

{
  "mcpServers": {
    "androidbuilder-mcp": {
      "command": "node",
      "args": [
        "C:/Users/User/.gemini/antigravity-ide/scratch/androidbuilder-mcp/dist/index.js"
      ],
      "env": {
        "BROWSER_DEBUG_PORT": "9222",
        "ANDROIDBUILDER_DEBUG": "0"
      }
    }
  }
}

Environment Variables

Tool Reference

get_project_info

No parameters required.

Returns:

{
  "projectName": "MyApp",
  "activeScreen": "Screen1",
  "isBlocksView": false,
  "isDesignerView": true,
  "ideType": "AndroidBuilder",
  "url": "https://androidbuilder.in/ode/..."
}

get_component_tree

Returns:

{
  "screen": "Screen1",
  "tree": [
    {
      "name": "Screen1",
      "type": "Form",
      "children": [
        { "name": "Button1", "type": "Button" },
        { "name": "Label1", "type": "Label" }
      ]
    }
  ]
}

get_component_properties

Note: Click the component in Designer view first to populate the Properties panel.

update_component_property

add_blocks

Requires: Blocks view

get_blocks_xml

No parameters. Exports current workspace as XML.

clear_blocks

No parameters. Clears all blocks (irreversible via MCP).

switch_screen

list_screens

No parameters. Returns all screen names in the project.

click_element

Troubleshooting

Failed to connect to Chrome CDP

• Chrome was not started with --remote-debugging-port=9222

• Another process is using port 9222

• Check BROWSER_DEBUG_PORT env var

No active AndroidBuilder/App Inventor tab found

• Open a project in the IDE before calling any tool

• The IDE page must be fully loaded, not just navigated to

Component tree (.gwt-Tree) not found

• You are in Blocks view — switch to Designer view

Blockly is not available

• You are in Designer view — switch to Blocks view

Tools hang / timeout

• Increase EVAL_TIMEOUT_MS (default 15000ms)

• Reload the IDE page and try again

Development

# Build
npm run build

# Run with debug logging
ANDROIDBUILDER_DEBUG=1 node dist/index.js

# Run with custom port
BROWSER_DEBUG_PORT=9223 node dist/index.js

Supported IDEs

• AndroidBuilder

• MIT App Inventor 2

• MIT App Inventor (code)

• Niotron

• Kodular

• AppyBuilder

License

MIT