{"version":"2.1.319","anchor":"cache-break-detection-refactored-with-a-peek-function","canonical_anchor":"cache-break-detection-refactored-with-a-peek-function","heading":"Prompt-cache tracking now checks settings one by one","tier":"internal","area":"Prompt Cache","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.319\/e\/cache-break-detection-refactored-with-a-peek-function","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.319","markdown":"### Prompt-cache tracking now checks settings one by one\n\nClaude Code's tracking of when the prompt cache stops being reused now fingerprints each setting separately and drops a system prompt comparison\n\n**What**\n\nThe prompt cache lets the model reuse work from earlier requests when the start of a request has not changed. Claude Code keeps track of when that reuse breaks. The tracker now:\n\n- records a fingerprint (a hash) for each setting separately\n\n- can look at its current state without changing it\n\n- keeps the fingerprint of the tools list\n\nIt no longer compares the system prompt fingerprint it had stored.\n\n**Why**\n\nThis is internal reporting about cache use, not a change to how the cache works.\n\n- Area: Prompt Cache\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}