You'll noticeTier: how much it should matter to you
3Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
SubagentsArea: what it touches
Bug FixesKind: in v2.1.285,
Bug FixesSection of the release
What
Plan mode is a mode where Claude plans its work for your approval before making changes. Only your main session can enter it, not a subagent (a helper that Claude starts to handle part of a task). Before, a subagent trying to enter plan mode caused an internal error while the EnterPlanMode tool ran. Now the request is checked before it runs and refused with the message "Only the main session can enter plan mode."
Why
The subagent now gets a clean, readable refusal instead of a crash-style error, so it can carry on with its task.
