TaskStop can stop a named background agent by name, and teammate ids are called addresses
TaskStop's instructions now say a named background agent can be stopped by name, and the ambiguous-teammate error asks for the full address (name@team)
You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
Agent TeamsArea: what it touches
ImprovementsKind: in v2.1.290,
ImprovementsSection of the release
What
TaskStop is the tool Claude uses to stop work running in the background. A teammate is another Claude process working in an agent team, and a background agent is a helper Claude starts to work on its own.
TaskStop's description, the instructions Claude receives about the tool, gains a line: "To stop a background agent spawned with a name, pass that name as task_id".
The teammate line drops the ("name@team") format hint. It now reads: pass the teammate's agent ID or bare teammate name as task_id. In the prompt captured under this release, the description is 364 characters.
When a name matches more than one teammate, the error now asks for the "full address (name@team)" instead of the "full agent ID". The version that also mentions background agents says to use the full address for the teammate or the task ID for the background agent.
Why
Claude can now stop a background agent you started with a name by using that name. The error wording now matches how teammates are referred to elsewhere.
How sure we are
One source agreesOne thing we can check says the same as this entry.
Anthropic's release notes agreeChanged an in-process teammate's agent_id in Agent results to its agent ID (its name@team address stays in teammate_id); TeammateIdle hooks…
