[pfraze]

There's actually nothing stopping you from using your own verbs, actually; it's allowed. Lloeki gives a good reason not to, though: I don't know how PAY will be handled without consulting documentation.

[bluesnowmonkey]

The HTTP spec is -- it only specifies certain verbs. An implementation need not (and often doesn't) support others.

[scoot]

Isn't how any of the supported HTTP verbs is handled dependant on the API? <consults documentation...>

[pfraze]

Yeah, but not totally. For instance, you can always guess what a GET does. There are properties of the established verbs that you can expect.