I did not experience hallucinations (very rarely if at al) when I use it for programming. It happened more with niche languages (so I provide examples and documentation), and with GPT.

Let us say there is 3k lines of RFCs, API, documentation of niche languages, examples), 2k lines of code generated by Claude (iteratively, starting small), then I do exceed the limit after a while. In that case I ask it to summarize everything in detail, start a new chat, use those 3k lines and the recent code, and continue ad infinitum.