{"version":"2.1.285","anchor":"compaction-summary-now-returns-content-plus-optional-modelon","canonical_anchor":"compaction-summary-now-returns-content-plus-optional-modelon","heading":"Compaction summary can carry a separate note meant only for the model","tier":"internal","area":"Compaction","url":"https:\/\/changelogs.core-directive.com\/v\/2.1.285\/e\/compaction-summary-now-returns-content-plus-optional-modelon","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.285","markdown":"### Compaction summary can carry a separate note meant only for the model\n\nThe message built after compaction can now hold a second, model-only text, though nothing fills it in yet\n\n**Unclear.** It is not clear where, if anywhere, the model-only text is set.\n\n**What**\n\nCompaction is when Claude Code shortens a long conversation by replacing earlier messages with a summary. The message it builds after compacting used to be plain text. It now has two parts: the visible content, and an optional text intended only for the model. The part that builds this message never fills in the model-only text.\n\n**Why**\n\nNothing changes for now, since the model-only part is left empty. It looks like preparation for text that the model sees but the reader does not.\n\n- Area: Compaction\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 3\/5\n- Present in the build but not switched on"}