docs: private String buildStartMessage(RecognizeOptions options) {
      Gson gson = new GsonBuilder()
          .setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES)
          .create();
      JsonObject startMessage = new JsonParser().parse(gson.toJson(options)).getAsJsonObject();
      startMessage.remove(MODEL);
      startMessage.remove(CUSTOMIZATION_ID);
      startMessage.remove(LANGUAGE_CUSTOMIZATION_ID);
      startMessage.remove(ACOUSTIC_CUSTOMIZATION_ID);
      startMessage.remove(VERSION);
      startMessage.addProperty(ACTION, START);
      return startMessage.toString();
    }