def METHOD_NAME(self, instance):
    invalid_nodes, message = self.get_invalid_with_message(instance)
    if invalid_nodes:
        # instance_node is str, but output_node is hou.Node so we convert
        output = instance.data.get("output_node")
        output_path = output.path() if output else None
        raise PublishXmlValidationError(
            self,
            "Invalid VDB content: {}".format(message),
            formatting_data={
                "message": message,
                "rop_path": instance.data.get("instance_node"),
                "sop_path": output_path
            }
        )