In Creating Activedocs when activedocs is being created from a file, the list item states "Filename in the available path" . The file formats that can be used for <specification> should be listed - similar to importing activedocs section.  Explicitly listing would remove any (erroneous) assumption that a reader might make that only JSON files are allowed just like 3scale API  "POST /admin/api/active_docs.json" for creating activedocs in JSON format