Yesterday I added a Webmention form at the bottom of my posts. If you used this form, it would show you a "check status" link after accepting the Webmention request. My Webmentions are all handled by webmention.io, and its status URLs return a JSON response. This isn't particularly friendly when someone views one of these URLs in a browser, since they just see a raw JSON blob.
Today I updated webmention.io to return all responses in HTML if they're made from a browser. It checks to see if there is text/html in the Accept header, and returns HTML if so, otherwise returns JSON as normal. Now when you view one of these status links, you'll see something like this.
![](https://aaronparecki.com/2016/12/30/5/image-1.png)
Since the Webmention spec doesn't define the body of the response, doing this is still considered conformant to the spec. The one non-standard thing I had to do was to return an HTTP 303 response when accepting the Webmention instead of 201, in order to get the browser to redirect to the status URL immediately. I still return 201 to non-browser clients so they won't see any change.