I built a Python AI agent and Pylance drove me to build a type checker and LSP

A while back I started building Nimble Agent — a LangChain-based coding agent in Python. The idea was to fix the things that annoy me about other AI agents: smarter prompting, cheaper models, and acceptance criteria so the agent can't just hand-wave "done" and stop.

It's an AI agent that writes code. Which means the one thing I could not afford was my own code lying to me about its types.

So I tried the standard Pylance extension and Pyright as a type checker. I was seriously underwhelmed.

Skip the hype. Install the extensions here:

VSCode