private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.vertexai.api.ExplanationMetadataOverride,
            com.google.cloud.vertexai.api.ExplanationMetadataOverride.Builder,
            com.google.cloud.vertexai.api.ExplanationMetadataOverrideOrBuilder>
        getMetadataFieldBuilder() {
      if (metadataBuilder_ == null) {
        metadataBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.vertexai.api.ExplanationMetadataOverride,
                com.google.cloud.vertexai.api.ExplanationMetadataOverride.Builder,
                com.google.cloud.vertexai.api.ExplanationMetadataOverrideOrBuilder>(
                getMetadata(), getParentForChildren(), isClean());
        metadata_ = null;
      }
      return metadataBuilder_;
    }
<pre>
The metadata to be overridden. If not specified, no metadata is overridden.
</pre>

<code>.google.cloud.vertexai.v1.ExplanationMetadataOverride metadata = 2;</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/ExplanationSpecOverride.java