This is the descr field on the domain's identity FSM, a short auto-generated text summary of what the current FSM run is doing or has just done. Because this text is generated by UCS Manager itself (not typed by an admin), it's the quickest human-readable clue to what step of the identity workflow is executing without having to decode the stage table separately. It might read something like 'Syncing identity database with peer fabric interconnect' while that step is in progress.