· Agents
Agents in parallel, and delegation that nests
A session can run several agents at once and delegate one level deeper, with the concurrency proved by overlap rather than assumed.
Delegation was sequential and one level deep. Both limits were arbitrary: a session that needs three files read has no reason to read them one after another.
Runs now overlap, and a delegated agent can delegate in turn. One run's cleanup cannot evict its siblings, which was the failure mode that made the first attempt at this untrustworthy.
The concurrency test proves overlap directly rather than inferring it from wall-clock time. A timing assertion on a loaded machine measures the machine.