The interactions between an application and a FRS include not only the set of interface functions such as get-slot-values , but also a set of names of built-in frames, slots, and facets. To provide applications with a uniform model, the Generic Frame Protocol specifies standard names for some frames, slots, and facets. These names are taken from the Frame Ontology, in which they are defined by a formal axiomatization [], and the specification of basic data types in the Knowledge Interchange Format [].
All of the standard names are symbols in the keyword package. This approach avoids package conflicts and emphasizes that these are built in to the Generic Frame Protocol.