You'll noticeTier: how much it should matter to you
1Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
AgentsArea: what it touches
ImprovementsKind: in v2.1.321,
ImprovementsSection of the release
What
A subagent is a helper that Claude starts to work on part of a task. If a message is on its way to a subagent and the subagent is stopped in the meantime, Claude Code now drops the message with an error saying it was stopped meanwhile. Before, this was refused only when you had stopped the agent yourself.
MCP tools, which are outside tools connected through the Model Context Protocol, can be moved to the background when they run long. That move now also waits while something holds it back.
Why
It avoids reviving a subagent that was stopped just as a message reached it.
