Nope, you gotta understand. This is the move. It is appended at the end of every single message. It is never saved in the conversation that get sent back for inference. So you send it. But when you go back for inference, it’s at the top of the stack so all of the cashing works you’re not pre-filling every time or anything like that. It burns plus N tokens, where N is my prompt stack. It is not really that expensive. I have measured it to within an inch of it its life. Think of it this way every bit of the prefix and the conversation stays exactly the same you’re only adding to the very end of the conversation. So after the first turn, it is basically always cashing within the KV cache for a given context. Sorry I am using voice dictation. My hands are tired this week. Basically you sculpt the conversation history to ensure prefix caching
Yes - with arbitrary prefix caching that might work. That's tricky though, not everyone is going to provide that.
Did you have to build your own harness for this? Or hack Claude Code or something?
I don’t use their CLIs. OMP/OpenCode. If you are stuck on them, you can do it in a proxy layer.