@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (mode_
        != com.google.cloud.vertexai.api.FunctionCallingConfig.Mode.MODE_UNSPECIFIED.getNumber()) {
      output.writeEnum(1, mode_);
    }
    for (int i = 0; i < allowedFunctionNames_.size(); i++) {
      com.google.protobuf.GeneratedMessageV3.writeString(
          output, 2, allowedFunctionNames_.getRaw(i));
    }
    getUnknownFields().writeTo(output);
  }
<pre>
Optional. Function names to call. Only set when the Mode is ANY. Function
names should match [FunctionDeclaration.name]. With mode set to ANY, model
will predict a function call from the set of function names provided.
</pre>

<code>repeated string allowed_function_names = 2 [(.google.api.field_behavior) = OPTIONAL];
</code>

@param index The index of the value to return.
@return The bytes of the allowedFunctionNames at the given index.
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/FunctionCallingConfig.java