API ReferenceAdd-ons
Overview
Create checkout add-ons and manage the products, courses, and bookings that offer them.
Add-ons are optional extras offered at checkout. Assign them to the products, courses, or bookings that should offer them.
New add-ons are always created as drafts and can initially have no variants. Create exactly one published, fixed-price, single-payment variant through the product variant endpoints, then publish the add-on by setting is_draft to false.
When replacing an add-on's parent products or a product's add-ons, send the whole list of IDs in the order you want, not just the changes. Every referenced resource must belong to the selected store. Subscription products cannot offer or participate in add-on relationships.