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
The description of the Agent tool was rewritten in the prompt Claude Code sends with its reminder about the to-do list. The Agent tool is how Claude passes work to a subagent, a separate helper copy of Claude.
The new text gives Claude a default for unclear cases: "When in doubt, don't spawn."
Why
This text is part of Claude's own instructions, so the rewrite changes how often Claude starts helpers. When the choice is unclear, it is now told to do the work itself.
