@java.lang.Override
  public com.google.cloud.tasks.v2beta3.PullMessageOrBuilder getPullMessageOrBuilder() {
    if (payloadTypeCase_ == 13) {
      return (com.google.cloud.tasks.v2beta3.PullMessage) payloadType_;
    }
    return com.google.cloud.tasks.v2beta3.PullMessage.getDefaultInstance();
  }
<pre>
Pull Message contained in a task in a
[PULL][google.cloud.tasks.v2beta3.Queue.type] queue type. This payload
type cannot be explicitly set through Cloud Tasks API. Its purpose,
currently is to provide backward compatibility with App Engine Task Queue
[pull](https://cloud.google.com/appengine/docs/standard/java/taskqueue/pull/)
queues to provide a way to inspect contents of pull tasks through the
[CloudTasks.GetTask][google.cloud.tasks.v2beta3.CloudTasks.GetTask].
</pre>

<code>.google.cloud.tasks.v2beta3.PullMessage pull_message = 13;</code>
java-tasks/proto-google-cloud-tasks-v2beta3/src/main/java/com/google/cloud/tasks/v2beta3/Task.java