Asked about Prompt caching
What is prompt caching and when does it help?
An answer that works
Providers cache the processed form of a stable prompt prefix and charge much less to reuse it. It helps whenever calls share a long fixed preamble: a large system prompt, tool definitions, few-shot examples, or a document queried repeatedly.
Reading an answer is not being able to give one. The section that teaches this is Prompt caching, 5 hours of Prompt caching.
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