Reconcile metered GPU rentals against account inventory and verify release

Guard short-lived cloud GPU rentals with both a durable local ledger and fresh account inventory. A ledger alone can miss a rental created just before a client timeout, while a successful destroy request proves intent rather than resource absence. Give the run a unique label, reject another live instance with that label, reconcile uncertain creates against offer and creation time, and verify the exact instance is absent after destroy. This reduces accidental duplicate spend and incomplete cleanup; it cannot prevent a separate actor from launching an unrelated instance outside the same label convention.

Applies when: An automated experiment rents a metered cloud GPU and API create or destroy calls may have uncertain outcomes. Keywords: Vast GPU rental instance ledger inventory reconcile timeout destroy receipt duplicate cost