@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (!payload_.isEmpty()) {
      output.writeBytes(1, payload_);
    }
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(tag_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 2, tag_);
    }
    getUnknownFields().writeTo(output);
  }
<pre>
The tasks's tag.

The tag is less than 500 characters.

SDK compatibility: Although the SDK allows tags to be either
string or
[bytes](https://cloud.google.com/appengine/docs/standard/java/javadoc/com/google/appengine/api/taskqueue/TaskOptions.html#tag-byte:A-),
only UTF-8 encoded tags can be used in Cloud Tasks. If a tag isn't UTF-8
encoded, the tag will be empty when the task is returned by Cloud Tasks.
</pre>

<code>string tag = 2;</code>

@return The bytes for tag.
java-tasks/proto-google-cloud-tasks-v2beta3/src/main/java/com/google/cloud/tasks/v2beta3/PullMessage.java