Alerts

Rules are stored with their owner, source, threshold and cooldown, and evaluated by deterministic code. Missing or stale data is reported as unknown, never as a trigger.

Background monitoring

How evaluation works

Threshold rules trigger on the crossing and re-notify at most once per cooldown while the condition holds.
A stale reference price does not evaluate price thresholds; use a feed-age rule to be told about staleness.
Session rules record the first state silently and notify on later transitions.
Each notification is bound to the observation that produced it, so retries never duplicate it.

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