Not using HTTP codes is much, much worse. I've dealt with SOAP/RPC APIs that return nothing but 200, no matter what. The actual status is an english word in

Not using HTTP codes is much, much worse. I've dealt with SOAP/RPC APIs that return nothing but 200, no matter what. The actual status is an english word in the response body (i.e. OK, ERROR, etc.) That is a nightmare to deal with because you have to manually decode each and every request instead of using a library to do the heavy lifting for you. Sometimes I have questions on which HTTP status code to use, but most of the time its pretty clear. And if you stick to the official codes most client side libraries will just work without any drama at all. As a bonus, all of the intermediate processes (proxies, firewalls, CDNs, etc.) will work as well without any finagling on your part. :)