subagent-stall-root-causes-and-bulletproofing

Subagent stalls have four distinct root causes: (1) settings.local.json missing Edit/Write wildcards forces permission prompts on every file modification — zero Edit/Write entries was the actual state before this fix; (2) isolation:worktree writes to temp git worktree, changes don’t persist to live tree; (3) session-scoped MCPs registered mid-session are not visible to subagents started before; (4) non general-purpose agent types have curtailed toolsets. Fix: broad wildcard permissions in settings.local.json, never pass isolation:worktree for production, always use subagent_type:general-purpose.