action (BookReservaton) {
  type(Search)
  description (Book a reservation)
  collect {

    // Ask for the user's reservation date
    input (reservationDate) {
      type (time.DateTimeExpression)
      min (Required) max (One)
    }

    // Prompt for number of guests, but also allow them to confirm 2
    input (numberOfGuests) {
      type (NumberOfGuests)
      min (Required) max (One)
      default-init {
        intent {
          goal: NumberOfGuests
          value: $expr(2)
        }
      }
      prompt-behavior (AlwaysSelection)
    }
  }
  output (Reservation)
}