Reports one JobDiva BI feed's SHAPE - row count, column names, a sample row - for a date window. Read-only, stores nothing. Use it before wiring any feed into the poll. Every field failure in this integration came from assuming a column name and finding out later that the wire disagrees; UpdatedHires keys on PLACEMENTID rather than "start id", and that silently dropped every placement for a month. The feed is named from a fixed allow-list, never a path: this call carries the tenant's JobDiva credentials.