You'll noticeTier: how much it should matter to you
1Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
SubagentsArea: what it touches
ImprovementsKind: in v2.1.307,
ImprovementsSection of the release
What
Compaction is when Claude Code shrinks a long conversation by summarising it. The Agent tool lets Claude hand a task to a subagent, a separate helper that returns a summary. The tool's description in the compaction prompt has been rewritten.
The old text mainly listed when to delegate. The new text asks Claude to weigh what a subagent costs against the accuracy it adds. It points out that you pay for agents Claude did not need, and pay again for work Claude redoes because it skipped one.
The standard Agent tool description is unchanged.
Why
These are instructions Claude follows, so they may change how often it starts subagents. That effect has not been measured.
