Caching Stable Prompt Prefixes for Agents

A provider can reuse the unchanged front of a prompt across calls, which cuts both cost and latency when an agent sends the same instructions, tool schemas and older history on every turn. The catch is that a cache is keyed on the exact prefix, so one changing value near the top throws everything behind it away. This skill covers ordering a prompt so the stable parts come first, the things that commonly break a cache, and how to confirm the cache is actually being used rather than assuming it.

Commands