@java.lang.Override
  public Builder toBuilder() {
    return this == DEFAULT_INSTANCE ? new Builder() : new Builder().mergeFrom(this);
  }
<pre>
Optional. The retrieval config for the Rag query.
</pre>

<code>
.google.cloud.vertexai.v1.RagRetrievalConfig rag_retrieval_config = 6 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/VertexRagStore.java