code: protected ModelNode getReplyValueTypeDescription(ResourceDescriptionResolver descriptionResolver, Locale locale, ResourceBundle bundle) {
          // bug -- user specifies a complex reply type but does not override this method to describe it
          return new ModelNode(ModelType.OBJECT); //todo rethink this
          //throw MESSAGES.operationReplyValueTypeRequired(operationName);
      }
docs: Hook for subclasses to provide a description object for any complex "value-type" description of the operation reply.
  <p>This default implementation throws an {@code IllegalStateException}; it is the responsibility of
  subclasses to override this method if a complex "value-type" description is required.</p>
  
  @param descriptionResolver resolver for localizing any text in the description
  @param locale              locale for any text description
  @param bundle              resource bundle previously {@link ResourceDescriptionResolver#getResourceBundle(Locale) obtained from the description resolver}
  @return a node describing the reply's "value-type"
  @throws IllegalStateException if not overridden by an implementation that does not