Most recent completed bucket at the key plan granularity, with only the plan-entitled columns. ROW QUALITY: whenever qualityFlags is in the projection the response carries a quality object as a SIBLING of values (never inside it) — { raw, all, flags, contaminates, observedAt }. raw is the bitmask ORed across the bucket and all the same ANDed; flags names the bits set in raw; contaminates lists the metric families they call into question, so a broken order book can leave the trade columns of the same row sound; observedAt is epoch ms for when the book was actually read. It is present on a clean row too, as raw 0 with empty lists. The raw integer also stays in values.qualityFlags as a plain number. Decode with the bits table on the qualityFlags entry of GET /v1/catalog.