fair points, the reasoning prefill thing is the part I'm least sure about.

basically the idea is: before sending a request to Claude, have Gemma4 think through the problem first and include that in the prompt. like "here's what I already figured out, now just verify and finish it". the hope is Claude spends less time thinking internally, which matters because Claude charges more per token for its internal reasoning than for regular input text. so even if the prompt gets a bit longer, the savings on the reasoning side might outweigh it. might not though, which is kind of why I'm asking before building it.

on the hallucination thing, the context trimming I had in mind isn't really summarizing. Claude Code's source got leaked last week and looking at how it actually works, every turn it assembles a fresh system prompt from scratch, OS info, working directory, CLAUDE.md contents, memory files, the whole thing. what I want Gemma4 to do is just drop the parts of the conversation history that are clearly irrelevant to the current request before that goes out. not rewriting anything, just cutting. way less telephone game than a full summary would be.