Models work best when they have short instructions and no noise. "Conversation [may] contain" also means "conversation has a lot of noise". It degrades performance and increases cost.
I use handoff skill to ask model to write a prompt for itself.
I use handoff skill to ask model to write a prompt for itself.
I've found Opus 5 far better as a subagent with very limited context window use, which could suggest that it might not have good long context performance unlike its predecessors. (I was one of many tearing my hair out trying to work with Opus 5 for the past week.)