Which AI tool do you use/recommend for firmware development?

I have tried a few tools, even though I can’t copy paste or upload download to them, due to security restrictions at work.

in my experience, ChatGPT free version is good for generic advice, tool chain advice and peripheral configuration of MCUs, even without providing the mcu manuals.

Claude creates clean readable code, but often messes up register names etc. (at least in the free version where I can’t give it more context via file uploads)

I would like hear what others have to say on this topic.