{"version":"2.1.246","anchor":"warning-when-a-custom-endpoint-is-not-caching-your-prompts","canonical_anchor":"warning-when-a-custom-endpoint-is-not-caching-your-prompts","heading":"Warning when a custom endpoint is not caching your prompts","tier":"notice","area":"API Endpoints","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.246\/e\/warning-when-a-custom-endpoint-is-not-caching-your-prompts","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.246","markdown":"### Warning when a custom endpoint is not caching your prompts\n\nClaude Code now warns in the log when a custom endpoint is throwing away your prompt cache.\n\n**What**\n\nClaude Code now watches whether prompt caching is actually taking effect. After three turns in a row with 20,000 or more input tokens and essentially no cache being written or read, it logs a warning that a custom endpoint is discarding the cache, which shows up as slower, more expensive turns.\n\n**Details**\n\n- Emits `api_prompt_cache_coverage` with a `cache_coverage_loss` outcome plus the consecutive-turn count and token counts.\n- A one-time confirmation on the same event fires instead when caching is seen working.\n- The check runs for providers reached through a gateway, and conditionally for the first-party API.\n\n**Evidence**\n\n`sustained uncovered input with a cache breakpoint on the wire through a custom endpoint`\n\n- Area: API Endpoints\n- Tier: You'll notice\n- Useful: 4\/5\n- Signal: 3\/5"}