Comment by iamjackg

It's not unsolved, at least not the first part of your question. In fact it is a feature offered by all main LLM providers!

- https://platform.openai.com/docs/guides/prompt-caching

- https://platform.claude.com/docs/en/build-with-claude/prompt...

- https://ai.google.dev/gemini-api/docs/caching