[Pesthuf]

It’s a good option, but you can’t give users a reason for the failure. They might even assume your service is broken.

[booi]

I stopped listening on port 80 for everything… nobody’s complained yet! Maybe because they can’t find the service though.

[inopinatus]

I think it's fair to assume j. random user isn't typing "http://api.example.net" into their web browser.

leading www perhaps, leading api no.

[tracker1]

You'd be surprised... generally if there's a dedicated hostname for the API, I would expect / to either display or redirect to API docs.

Also, doesn't help when you're reverse proxying /api to $API/api

[inopinatus]

Posting on this forum means you are probably not J. Random User. I mean specifically anyone who will not grasp the difference between http:// and https://api.example.com.