Affirm Promos API

The Affirm Promos API is a server-side endpoint that enables merchants to render dynamic promotional pricing text and present Affirm-hosted educational modals on their website. It accepts a purchase amount and returns financing terms, "as low as" monthly payment messaging, APR rates, and modal content including headlines, descriptions, and legal disclosures. The API supports multiple installment term options and page-type context (product, cart, homepage) to customize the displayed messaging.