public com.google.cloud.vertexai.api.RetrievalConfig getRetrievalConfig() {
      if (retrievalConfigBuilder_ == null) {
        return retrievalConfig_ == null
            ? com.google.cloud.vertexai.api.RetrievalConfig.getDefaultInstance()
            : retrievalConfig_;
      } else {
        return retrievalConfigBuilder_.getMessage();
      }
    }
<pre>
Optional. Retrieval config.
</pre>

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

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