Hidden keeps the listing out of the org-visible catalog. Curation: a sync never changes it. Only a SuperAdmin sets it, and only a SuperAdmin sees a hidden entry listed.
ID addresses the listing in a URL. It is the reverse-DNS NAME with its one slash written as an underscore — reversible, because a namespace never contains an underscore — so the id is readable and stable rather than a hash that means nothing to whoever reads a link.
Official is whether this is the vendor's OWN server rather than someone else's copy of it. Derived on every sync (see isOfficial) until a SuperAdmin sets it explicitly, after which the admin's answer stands.
Transports are the distinct transports this server can be reached over, sorted: some of "stdio", "streamable-http", "sse". A listing with "streamable-http" is one an org can enable here and now; a listing that is only "stdio" needs a process to run it.