You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
CompactionArea: what it touches
ImprovementsKind: in v2.1.312,
ImprovementsSection of the release
What
A skill is a packaged set of instructions Claude can load. Compaction is when Claude Code shortens a long conversation by summarising it.
User messages can now carry an invokedSkill field.
When a skill is used, its message records invokedSkill with the skill's name and path. This applies only to skills run in the main conversation and not in a separate fork, and only when a feature check passes.
When compaction builds its list of skills used (the invoked_skills attachment), it now also scans the conversation for skills used and for messages with invokedSkill, and adds them back. Before, only the session's own record of used skills fed this list.
Restoring a skill also takes a timestamp.
Why
Skills used earlier in a conversation are more likely to stay available after compaction or when you resume a session.
