u-comment - optionally embedded (or nested?) h-cite(s), each of which is a comment on/reply to the parent h-entry.

The h-entry spec identified p-comment as a optionally embedded (or nested?) h-cite(s), each of which is a comment on/reply to the parent h-entry. Being as the URL would be proper for a citation in most cases, it should be a u proposal.

u-comment - identifies the element as a comment on the h-entry, for comment discovery when reading an h-entry. Optionally an embedded h-cite

There seem to be a sufficient amount of examples. https://indieweb.org/comments#IndieWeb_Examples