Yeah, I made a simple agent based on this tutorial:

https://minimal-agent.com/

It's slightly bigger now, but here's a ~50 line version for reference. I added the missing outer while-loop, so it takes user input etc.

https://gist.github.com/a-n-d-a-i/bd50aaa4bdb15f9a4cc8176ee3...

I mostly use it with GLM via their coding plan, I got a year for like $20 when it was on sale. But I also hooked it up to Sonnet, Opus, GPT, etc.