pydantic/monty

A minimal, secure Python interpreter written in Rust for use by AI.

Experimental - This project is still in development, and not ready for the prime time.

A minimal, secure Python interpreter written in Rust for use by AI.

Monty avoids the cost, latency, complexity and general faff of using a full container based sandbox for running LLM generated code.

Instead, it lets you safely run Python code written by an LLM embedded in your agent, with startup times measured in single digit microseconds not hundreds of milliseconds.

In short, Monty is extremely limited and designed for one use case:

To run code written by agents.

For motivation on why you might want to do this, see:

In very simple terms, the idea of all the above is that LLMs can work faster, cheaper and more reliably if they're asked to write Python (or Javascript) code, instead of relying on traditional tool calling. Monty makes that possible without the complexity of a sandbox or risk of running code directly on the host.

Note: Monty will (soon) be used to implement codemode in Pydantic AI

Monty can be called from Python, JavaScript/TypeScript or Rust.

(Or pip install pydantic-monty for the boomers)