{"version":"2.1.252","anchor":"incremental-claudemd-tool-description-context-diffing-i","canonical_anchor":"incremental-claudemd-tool-description-context-diffing-i","heading":"Incremental CLAUDE.md \/ tool-description context diffing ('instructions' attachments)","tier":"notice","area":"Context Management","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.252\/e\/incremental-claudemd-tool-description-context-diffing-i","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.252","markdown":"### Incremental CLAUDE.md \/ tool-description context diffing ('instructions' attachments)\n\nClaude Code now only re-sends changed CLAUDE.md\/instruction files instead of the whole block each turn, saving tokens.\n\nNew machinery (`RTt`, `PTt`, `dEt`, `pEt`, `yjt`) diffs the currently-announced set of CLAUDE.md\/instruction files against what was last sent, emitting a smaller 'instructions' attachment describing only what changed plus a list of removed files, instead of re-sending the full instructions block every turn. Messages include lines like 'Instruction files were re-read ...; these differ from their earlier copies' and 'Instructions no longer present: ...'.\n\nA companion 'prompt_snapshot' attachment type records the exact system prompt and tool descriptions sent, reused via `Use()`\/`BUn()` so unchanged tool descriptions don't need to be recomputed or re-sent (`recordedDescription` passed into `dA`\/`oie`).\n\n- Flag `tengu_carved_slate`: Off in both readings (read for one account on one subscription tier against v2.1.252; this account: off, anonymous baseline: off, compiled default: not a boolean we can read)\n- Area: Context Management\n- Tier: You'll notice\n- Useful: 3\/5\n- Signal: 3\/5"}