You'll noticeTier: how much it should matter to you
3Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
Plugin HooksArea: what it touches
ImprovementsKind: in v2.1.289,
ImprovementsSection of the release
What
Starting a named teammate (an agent that works alongside the main session) now goes through a plugin's agent.spawn hook, the plugin code that can block, rewrite or change the type of an agent launch. Before, teammates were started directly and skipped it.
When a hook rewrites a teammate launch:
Your permission rules are checked again against the rewritten launch
The hook cannot change the teammate into an agent type that does not run as a teammate
Required MCP servers (external tool integrations) are checked again
The event reported when the teammate starts now includes its agent id and model.
Why
A plugin that controls how agents are launched now covers teammates too, and your permission rules still apply to whatever the hook turns the launch into. This only matters when a plugin uses the agent-launch hook.
