Spotlight will diagnose issues on both the primary and standby systems. It'll also give you alerts and notifications when metrics fall outside of your thresholds. Here's a list of the canned alerts around Data Guard. It's a quick, at a glance, health check of your system.
This alarm is raised when an unacceptable number of logs on the Primary are waiting to be shipped through the Archiver to the Standby.
This alarm is raised when Spotlight on Oracle Data Guard has lost contact with one or more instances of the Oracle RAC (Standby connection). Spotlight on Oracle Data Guard will attempt to reconnect.
Keep Transport Lag low so your Recovery Point Objective can be met.
This alarm is raised when the Transport Processes have stopped for some reason.
So I encourage you to take a moment and look up a feature of Spotlight or your other toolsets. I still may never use the CD changer, but the weather has cleared up here in California so I think I'll open the sunroof.