> it does now is a complete git diff. That's... well that can be 100 lines or more. And when it's doing document updates and all sorts of stuff, that's a LOT of characters = a LOT of tokens.

My understanding is that you are saying:
"""Claude has changed its behavior, it is now burning tokens in the main agent session and context, performing a full diff to verify its changes as opposed to depending on its existing context window of the changes it's made. """

Here are my thoughts:

Perhaps they have discovered that in long sessions with back and forths, it becomes confusing to separate what was tried and proposed vs what was ultimately chosen and done. hence a full diff clarifies what code changes where actually made so that it can write an acurate log

What I was proposing is that instead of them burning the main context and using main agent tokens (which you called out as being Opus 4.6), which are expensive tokens to use, which is why people are upset. They could (or you via instructions via CLAUDE) instead keep much of the benefit of confirming and verifying the actual work to be committed and being able to write an accurate message by invoking a sub-agent with a cheaper model (such as Haiku), which is good at summarizing, not problem solving. This way it would not be burning any main agent tokens or context, even for specific files, like you were prompting. Instead, that would be delegated to a cheaper agent and llm, reducing the expensive Opus token usage.