The submit button in the post box says "add comment" vs. "reply" depending on what kind of message you're posting, and the link under comments says "reply" while articles don't have that link. I called it the "top-level descriptive comment on their Show HN post" because I agree just "comment" vs. "reply" alone could be confusing. What's a better way to describe the comment that an author posts with their Show HN to begin the discussion vs. replies that are made in response to specific comments? I genuinely don't know how many more terms I could have loaded onto that phrase to make it clear which post I was talking about. That wasn't supposed to be a confusing part of my post.