code: protected static boolean setCustomForDefaultProfile(String pathName, Boolean isResponse, String customData) {
          try {
              JSONObject profile = getDefaultProfile();
              String profileName = profile.getString("name");
              Client client = new Client(profileName, false);
              return client.setCustom(isResponse, pathName, customData);
          } catch (Exception e) {
              e.printStackTrace();
          }
          return false;
      }
docs: set custom request/response for the default profile's default client
  
  @param pathName friendly name of path
  @param isResponse true for response, false for request
  @param customData custom response/request data
  @return true if success, false otherwise