A validation tool (100) has a central body member (10) with threaded connections at each end (12, 13), as well as a central bore (11) extending there through. At least one battery powered video camera (20) or other optical data sensor is disposed along an outer surface of the body member and can be selective activated and de-activated. Optional mirror(s) (50) are provided to permit optimum viewing of the surrounding environment, while visual images and/or other sensed data is recorded and stored on at least one data storage media. The validation tool can be used for various purposes including wellbore integrity and verification that drilling mud has been fully displaced with completion fluid in a wellbore.