tric names.
   *     description {string}: Human readable description of the interval.
   *       Used to generate the metric descriptions.
   *     perSecond {boolean}: Whether metrics over this interval should be
   *       reported as per-second values (e.g. power). If not, integrated values
   *       over the whole interval (e.g. energy) are reported.
   *   }
   *
   */
  function* getRailStageIntervals_(model) {
    for (const exp of model.userModel.expectations) {
      const histogramName = exp.tit