Prompt caching stores repeated sections of AI prompts so systems avoid recomputing the same tokens on every call. The technique appears in APIs from providers such as Anthropic and OpenAI. It helps applications that send similar context repeatedly. Developers notice lower bills and faster replies when the same background text appears across multiple requests.
Limitations and Verification
Caching reuses computation for an eligible repeated prefix; it is not a stored answer. Automatic detection, explicit cache controls, token thresholds, retention and prices differ by provider and model. Cached input and cache writes can still be billed. Measure cache-hit tokens, total charges and latency using the same workload; do not assume a fixed saving or deterministic answers.
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