This page asks the engine directly when it loads, and again every minute while it is open.
What the states mean
Operational. The component's sources loaded at boot and answered the last lookup that used them. Some sources refusing is normal: a platform that rate-limits a request for an hour is counted as failed for that run and comes back on the next.
Degraded. More than a third of the sources failed on the most recent run. Reports still come back, with fewer lines and a sources panel that says which ones did not answer.
Down. No sources loaded for that component, or the breach index cannot be reached. A lookup of that kind will not run until it recovers; nothing is charged for a lookup that does not run.
When something is wrong
If a report came back thinner than you expected, the sources panel at the side of it lists every source asked and how each one answered — that is the first place to look. If the page above says a component is down, wait rather than retry: the lookup is refused before it costs anything, and a retry will not make it come back sooner.
Anything that does not match what you see here: contact us with the time and the kind of lookup.