@java.lang.Override
  public com.google.cloud.vertexai.api.ExplanationMetadata getMetadata() {
    return metadata_ == null
        ? com.google.cloud.vertexai.api.ExplanationMetadata.getDefaultInstance()
        : metadata_;
  }
<pre>
Optional. Metadata describing the Model's input and output for explanation.
</pre>

<code>
.google.cloud.vertexai.v1.ExplanationMetadata metadata = 2 [(.google.api.field_behavior) = OPTIONAL];
</code>

@return The metadata.
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/ExplanationSpec.java