Choose the API family
Match authentication and request behavior to the operation you are building.
Application onboarding
Merchant Sign-Up uses partner OAuth access tokens, packages, application data, consent and underwriting decisions. Existing merchant accounts that only need a gateway account use Account Management instead. Merchant sign-up workflow
Payment processing
Online and in-person operations include payments, invoices, saved payment methods and recurring billing. Use each operation’s documented credential and transport; endpoint families are not interchangeable. API reference
Account management and reporting
Account Management configures merchants, processors, services, fees and gateway settings. Reporting retrieves operational records and summaries. Administration covers credentials and event delivery. Partner v4 behavior