Text in HTTP headers

Question

Is there any rule against sending an alternate text for an HTTP response error? For example, a default is HTTP/1.1 400 Bad Request. When sending a header I set myself is it legal to do something like HTTP/1.1 400 Epic Fail?

Answer 1

It's fine. You can put any text there. You can even use special characters as long as you stick to ISO-8859-1 encoding.

From the RFC:

The reason phrases listed here are only recommendations -- they MAY be replaced by local equivalents without affecting the protocol.