For SOAP web services there is a specification which all request/responses must follow. This specification is in the form of a WSDL document. However for REST web services, why is there no such specification or WSDL? Does this make REST more vulnerable to runtime exceptions because we are not following any specifications?
There are bunch of ways to define a RESTful API just like WSDL for SOAP:
You can find more info here on my blog post.