You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
CompactionArea: what it touches
ImprovementsKind: in v2.1.311,
ImprovementsSection of the release
What
Compaction is when Claude Code replaces the older part of a conversation with a summary to free up space. A new notice reads: "Loaded from the session's last compaction, so the messages it summarized aren't here." Claude Code checks whether everything before the compaction point was kept before deciding the earlier messages are missing.
Why
When you open or resume a session that was compacted, you are told plainly that the earlier history is not shown, instead of being left to wonder where it went.
