Effects

A migration that ran, a cache that was invalidated, a notification that was sent: none leaves anything in the platform to read back, so no plan can say whether it already happened. A receipt makes it visible: an ordinary resource you declare, holding a hash of the effect’s input, that appears in your plan and tracks its own staleness.

PlatformHow an effect with nothing to read back is recorded
AWS A receipt: an ordinary resource, by convention an SSM parameter holding a hash of the effect’s input, that appears in your plan.
Kubernetes Not yet designed.