I added prompt caching to my Anthropic Batch API workflow. The hit rate was 0%.Each model has a minimum cacheable token ...

I added prompt caching to my Anthropic Batch API workflow. The hit rate was 0%.Each model has a minimum cacheable token count — 4,096 for Haiku 4.5. If your cache_control block is below that, the API silently ignores it. Successful response, zero cache reads, no warning.My IAB taxonomy prompt was 1,064 tokens. Well under the threshold.Full write-up:https://mikenoe.com/posts/prompt-caching-classivore/#AnthropicAPI #LLM #PromptCaching #AIEngineering