If you've written a response on your own site, you can enter that post's URL to reply with a Webmention.
The only requirement for your mention to be recognized is a link to this post in your post's content. You can update or delete your post and then re-submit the URL in the form to update or remove your response from this page.
Learn more about Webmentions.
Webmention is a way for you to tell me "Hey, I have written a response to your post."
Learn more about Webmentions at webmention.net