UDFS behavior regarding hard links and file IDs

Hello, I am observing the following behavior with UDFS:
when sending a “query hard links” request, it returns structures which are pairs of “parent dir file ID” and file name.
however, at the same time it doesn’t seem to allow “open by file ID”, so it seems the information returned by
“query hard links” is pretty useless since there is really no way to get the parent directory path out of the info returned.
Or am I missing something?