{"version":"2.1.317","anchor":"prompt-cache-ttl-gate-tengu-tidy-frost-keeps-a-5m-live-cache","canonical_anchor":"prompt-cache-ttl-gate-tengu-tidy-frost-keeps-a-5m-live-cache","heading":"Model check behind the shorter 5-minute prompt cache was reworked","tier":"internal","area":"Prompt Cache","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.317\/e\/prompt-cache-ttl-gate-tengu-tidy-frost-keeps-a-5m-live-cache","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.317","markdown":"### Model check behind the shorter 5-minute prompt cache was reworked\n\nClaude Code changed how it matches the current model against the set that a server-side switch can move from a 1-hour to a 5-minute prompt cache\n\n**What**\n\nThe prompt cache is Anthropic's servers keeping the earlier part of a conversation for a while, so it does not have to be processed again on every turn. A server-side switch can still shorten that cache to 5 minutes for a particular set of models, and subscribers otherwise get 1 hour, as before.\n\nWhat changed is how Claude Code checks whether the model in use belongs to that set. The rule itself, and its choice between 5 minutes and 1 hour, is the same.\n\n**Why**\n\nHow long the cache lasts affects how much a conversation costs to run and how quickly replies come back, so this matters to subscribers using the models in that set.\n\n- Flag `tengu_tidy_frost`: Not enough to say (read for one account on one subscription tier against v2.1.317; this account: no value returned, anonymous baseline: no value returned, compiled default: off) These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.\n- Area: Prompt Cache\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 2\/5\n- Scope: individual\n- Heads-up: no"}