public com.google.cloud.vertexai.api.FunctionCallingConfigOrBuilder
        getFunctionCallingConfigOrBuilder() {
      if (functionCallingConfigBuilder_ != null) {
        return functionCallingConfigBuilder_.getMessageOrBuilder();
      } else {
        return functionCallingConfig_ == null
            ? com.google.cloud.vertexai.api.FunctionCallingConfig.getDefaultInstance()
            : functionCallingConfig_;
      }
    }
<pre>
Optional. Function calling config.
</pre>

<code>
.google.cloud.vertexai.v1.FunctionCallingConfig function_calling_config = 1 [(.google.api.field_behavior) = OPTIONAL];
</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/ToolConfig.java