AndroidBuilder MCP Server

Local Model Context Protocol server for MIT App Inventor, AndroidBuilder, Kodular, Niotron, and AppyBuilder. It connects to a Chrome/Chromium session through the Chrome DevTools Protocol and can safely inspect AIA/AIX archives offline.

The server is safe by default: read tools are available immediately, while write tools require explicit environment flags.

Tools

Stashed changes | list_ide_tabs / select_ide_tab | Navigation | Explicit trusted-tab selection | | inspect_aia / validate_aia / diff_aia | Offline read | Safe project archive inspection | | inspect_aix / validate_aix | Offline read | Safe extension metadata inspection | | read_archive_entry | Offline read | Bounded single-entry read | | get_component_catalog / get_component_schema / search_components | Read | Provider-discovered component metadata | | get_block_diagnostics | Read | Counts, warnings, and orphaned value blocks | | take_screenshot | Read | Designer, blocks, or full-page PNG | | update_component_properties | Write | Verified sequential batch update |

All tool results include success. Errors include a stable code; mutation timeouts include outcome: "unknown" and must be verified before retrying.

Related MCP server: Chrome DevTools MCP

Requirements

• Node.js >=22.12

• Chrome or Chromium launched with remote debugging enabled

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

Open your App Inventor-family IDE and load the project in that Chrome session.

Install

npm install
npm run build

Run the server:

node dist/index.js

MCP Config

Use .mcp.json in this repository for local development:

{
  "mcpServers": {
    "androidbuilder-mcp": {
      "command": "node",
      "args": ["dist/index.js"],
      "env": {
        "BROWSER_DEBUG_PORT": "9222",
        "ANDROIDBUILDER_ALLOW_WRITE": "0"
      }
    }
  }
}

For clients that do not resolve relative paths from the repository root, replace dist/index.js with an absolute path.

Environment

Multi-IDE compatibility

<<<<<<< Updated upstream The server recognizes IDEs by exact hostname and exposes provider capabilities and a validated flag through get_project_info. Providers currently share conservative GWT/Blockly fallbacks; AppyBuilder is read-only. A recognized provider is not automatically validated—run live contract tests against a disposable project before advertising production support.

The server recognizes IDEs by exact hostname and exposes provider capabilities and a validated flag through get_project_info. MIT App Inventor, AndroidBuilder, Kodular, and Niotron adapters use isolated strategies; AppyBuilder is experimental and read-only. A recognized provider is not automatically considered validated—run the live contract suite against a disposable project before advertising production support.

Stashed changes

Codex, Claude, and Antigravity

• Codex plugin manifest: .codex-plugin/plugin.json

• Portable MCP config: .mcp.json

• Open Agent Skill: skills/androidbuilder-mcp/SKILL.md

See docs/compatibility.md for client-specific setup notes.

Comparison with appinventor-mcp

The useful transport-independent features from rhyumiranda/appinventor-mcp were adapted to the existing CDP bridge. See docs/appinventor-mcp-comparison.md for the architectural comparison, adopted features, and rejected high-risk RPC mutations.

Development

npm run build
npm test
npm pack --dry-run

npm test builds the server, runs a real MCP SDK smoke test, verifies write tools are gated, checks the no-Chrome error path, and validates package metadata.

Troubleshooting

• Failed to connect to Chrome CDP: start Chrome with --remote-debugging-port=9222.

• No active AndroidBuilder/App Inventor tab found: open a project in the debug Chrome session.

• Component tree (.gwt-Tree) not found: switch to Designer view.

• Blockly is not available: switch to Blocks view.

• Write tool rejected: restart the MCP server with ANDROIDBUILDER_ALLOW_WRITE=1.

Recognized IDEs

• AndroidBuilder

• MIT App Inventor 2

• MIT App Inventor Code

• Niotron

• Kodular

• AppyBuilder

License

MIT