JAgent
An AI agent written in Java using LangChain4j. It works similarly to Claude Code if you have used that before.
It's completely free to use. To use it, sign up for a free Mistral account and agree to training. You might need to put in a phone number to do the verification.
It generated a pretty good calculator app on the first try, so I'd say it works pretty well. I didn't need to make any changes to it.