You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
SubagentsArea: what it touches
ImprovementsKind: in v2.1.307,
ImprovementsSection of the release
What
The Agent tool lets Claude hand a task to a subagent, a separate helper that works on its own and returns a summary. Its description in the agent-claude prompt has been rewritten.
The old text mostly told Claude when to delegate: matching agent types, parallel work, reading across many files. The new text adds a warning about the two handoffs. It says the subagent knows only what Claude puts in the prompt, Claude sees only the summary that comes back, and detail is dropped both ways without either side knowing what the other missed.
The standard Agent tool description is unchanged.
Why
These are instructions Claude follows, so they can change how often it delegates and how fully it briefs a subagent. That effect has not been measured.
