Alerting
Every rule can be replayed against your history before it exists, and every evaluation is recorded after. When a page arrives you can see exactly why — and when one doesn't, you can see that too.
The surface
The preview runs the same code the scheduler runs, over the range you pick — per-window verdicts, would-fire spans and all. What the chart shows is what would have happened.

In motion
Rules evaluate every 60 seconds. Two consecutive breaches open the incident and send the notification with the observed value attached; two healthy windows resolve it without anyone clicking close.
What it does
One endpoint, one key. Traces, logs, metrics and sessions land on the same trace id from the first request.