The task-topology point highlights a subtle failure mode: physical isolation can make logically dependent tasks look independent. Two agents may have completely separate worktrees and still be coupled through a shared API contract, schema, dependency version, or architectural assumption. That suggests dependency detection should happen before execution, not only when branches reach the merge queue. Even a lightweight contract map could help the dispatcher identify likely coupling and decide whether tasks should run concurrently or against an explicit predecessor. Isolation prevents accidental filesystem interference, but it doesn't remove semantic dependencies. The more agents run in parallel, the more important that distinction becomes.