> It's a nightmare full of wrestling with the LLM when you try to tell it the version of the framework and that it changed a lot from the previous version and yadda yadda

Tip: Add a default instruction to look at the actial downloaded source code of the dependencies used (assuming you're not dealing with closed source dependencies). Have the agent treat it as your own (readonly) source code instead of relying on model training data and possibly mismatching documentation on the web. Then it just greps for the exact function signatures and reads the file based documentation.