This event is triggered when a redemption is made by a customer (or programmatically via SDK). This is often helpful if you are implementing a custom redemption interface. The event is passed a single object representing the redemption made. It will include the following attributes:

$(document).on("swell:redemption", function(redemption) {
  if (redemption.discountType === "product") {
    // add the free product to cart
    cartJS.add(redemption.appliesToId);
  } else {
    // control the display of the coupon code to your customers
    myCoolUI.showCouponCode(redemption.couponCode);

    // save the code for later (to display it on future page loads?)
    sessionStorage.setItem("most-recent-coupon", redemption.couponCode);
  }
});