Create a discount in a workspace. A code-type discount (the default) needs a unique code; a percentage discount needs percent; a fixed discount needs a positive amount.

Creating a discount publishes the code; it does not attach it to anything. The link between an order and a discount is a separate applied-discount record, written when a buyer redeems the code at checkout or when a ClickFunnels user applies it in the admin UI - which is why POST /api/v2/workspaces/{workspace_id}/orders takes no discount field and the discount_ids on an order are read-only. Writing applied discounts is not part of this API yet, and when it lands it will be that record you create rather than a discount field on the order. Until then an integration creates, reads, updates, expires and deletes discounts, and reads back which orders ended up carrying them.