{"version":"2.1.261","anchor":"new-telemetry-prefix-break-diagnostics-with-sampled-hashing","canonical_anchor":"new-telemetry-prefix-break-diagnostics-with-sampled-hashing","heading":"New telemetry: prefix-break diagnostics with sampled hashing","tier":"internal","area":"Prompt Caching","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.261\/e\/new-telemetry-prefix-break-diagnostics-with-sampled-hashing","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.261","markdown":"### New telemetry: prefix-break diagnostics with sampled hashing\n\nNew sampled telemetry records detailed hashes around cache-prefix breaks.\n\nA new `tengu_prefix_break_hashes` telemetry event records detailed per-message-block hashes and diffs (types, roles, folded attachment info) around a cache-prefix break. It's gated by a sampling rate read from remote config, limited to first-party API usage, and excluded for HIPAA accounts.\n\n- Area: Prompt Caching\n- Names: `tengu_prefix_break_hashes`\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5"}