Starlark MCP Server

An MCP (Model Context Protocol) server that provides Starlark code execution capabilities to LLM clients.

Starlark is a Python-like language designed for safe, hermetic execution of untrusted code. This makes it an attractive option for executing LLM-generated code.

Programs can emit text output using the print() function, which is captured and returned to the LLM client. Output is limited to 16KB.

The server augments Starlark with some builtin functions.

Installation

You can install the server using go install:

go install github.com/alexmdac/starlark-mcp@latest

Usage

This server is designed to be used as a plugin for an MCP-compatible agent, such as Claude Code or Gemini.

Once installed, you can register it with your agent.

For Claude Code:

claude mcp add starlark-mcp starlark-mcp

For Gemini:

gemini mcp add starlark-mcp starlark-mcp

After registration, the agent will be able to use the execute_starlark tool provided by this server.

A good first prompt to try is: "generate a fractal using the Starlark MCP server".

License

This project is licensed under the MIT License - see the LICENSE file for details.