{"version":"2.1.299","anchor":"telemetry-event-tool-redescribed-when-a-tool-description-c","canonical_anchor":"telemetry-event-tool-redescribed-when-a-tool-description-c","heading":"Claude Code now records when a tool's description changes during a session","tier":"internal","area":"Telemetry","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.299\/e\/telemetry-event-tool-redescribed-when-a-tool-description-c","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.299","markdown":"### Claude Code now records when a tool's description changes during a session\n\nClaude Code now logs a diagnostic event when a tool's description differs from the one recorded earlier in the session\n\n**What**\n\nEach tool Claude can use comes with a description the model reads. Claude Code now checks whether any of these descriptions has changed since it was first recorded in the session, and logs a `tool_redescribed` event when one has. Tools that are loaded only when needed are not checked.\n\n**Why**\n\nThis is a diagnostic. The prompt cache lets Claude reuse the start of a conversation it has already processed, which saves time and cost, and a tool description changing partway through breaks that reuse. The event helps track down when that happens.\n\n- Area: Telemetry\n- Tier: Under the hood\n- Useful: 2\/5\n- Signal: 3\/5\n- Scope: individual\n- Heads-up: no"}