1 min lesson
Freshness as a declared SLA
Give the practical answer to "What does a freshness policy give you that a separate monitoring tool watching the same table does not?" Then name the detail that supports it.
Step 1 of 2
Freshness as a declared SLAstop writing alerting glue by hand
A freshness policy (and the freshness checks that enforce it) lets you state an SLA on the asset itself: “gold_daily_active must be no more than 90 minutes behind its data.” Dagster evaluates it and flags the asset as overdue, so the SLA lives next to the definition instead of in a separate monitoring system that drifts out of sync.
Auto-materialization closes the loop: declare a policy and Dagster materializes an asset when its upstreams change or its freshness window is about to lapse, without a hand-written schedule for every node. You describe the desired state of the graph and let the system keep it true.