It's a  hangover from old versions of AMS Designer. In the past, the elaborator needed to know what analog primitives were available, so that it knew that these would be supplied later on by the simulator (e.g. any transistor level models) - to do this you had to create an "Analog Primitive Table" (APT) file - there was a tool to do this from spectre models.

However, this has not been needed for many releases now.

Regards,

Andrew.