Observability

The property of a system whose internal state can be inferred from what it emits — logs, metrics, traces — well enough to answer a question nobody thought to ask when it was built

Distinct from monitoring, which watches for the failures you predicted. Here it is the evlog wide-event work (one structured event per request), the Sentry entry in the registry, and the analytics reports fed back into the site's own charts: three different emitters, one question — what is actually happening.