Claude Prompt Caching: One Ordering Mistake Breaks Every Call

Why is your Claude prompt cache hit rate so low? This field guide walks through every root cause: prefix matching rules, TTL windows, ordering mistakes, and the changes that silently invalidate everything. By the end you will know exactly where your misses come from and how to fix them. Chapters 0:00 Intro 0:24 How a hit works 1:20 The TTL clock 2:23 Prompt ordering 3:18 Invalidation triggers 4:06 Wrong tool scenarios 5:01 Measuring hit rate Sources (official docs) https://platform.claude.com/docs/en/b... https://platform.claude.com/docs/en/b... Support the channel: https://buymeacoffee.com/techwithdarin #FieldGuide