Every knowledge graph shared as static KGX formatted files will be indexed using agreed upon Translator Registry metadata which includes Provider Metadata (which includes data access particulars) and Content MetaData.
While processing Biolink Knowledge Graph data of diverse source and original formats, the Biolink KGX application generates output similar to this sample file. Thus, KGX tool generated output could be adapted to generate the content metadata.
The KGE metadata specification should ideally align as closely as sensible to the proposed new TRAPI Knowledge Map endpoint.