Observed source change · Anthropic
Claude prompt cache policy and minimums documentation changed
Published documentation; runtime behavior and legal interpretation not established.
Last unchanged check: 2026-10-21T18:50:10Z
First changed check: 2026-10-21T20:55:11Z
Before
* **[Automatic caching](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#automatic-caching)**: Add a single `cache_control` field at the top level of your request. The system automatically applies the cache breakpoint to the last cacheable block and moves it forward as conversations grow. Best for multi-turn conversations where the growing message history should be cached automatically. * **[Explicit cache breakpoints](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#explicit-cache-breakpoints)**: Place `cache_control` directly on individual content blocks for fine-grained control over exactly what gets cached. 3. Otherwise, it processes the full prompt and caches the prefix once the response begins. * 5-minute cache write tokens are 1.25 times the …
After
* **[Automatic caching](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#automatic-caching):** Add a single `cache_control` field at the top level of your request. The system automatically applies the cache breakpoint to the last cacheable block and moves it forward as conversations grow. Best for multi-turn conversations where the growing message history should be cached automatically. * **[Explicit cache breakpoints](https://platform.claude.com/docs/en/build-with-claude/prompt-caching#explicit-cache-breakpoints):** Place `cache_control` directly on individual content blocks for fine-grained control over exactly what gets cached. 3. Otherwise, it processes the full prompt and caches the prefix once the response starts. * Cache write tokens with a 5-minute TTL are …
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