The way in which the API specifications have been structured, allows the API Centre to mandate a core set of functions that API Providers must support when they implement the API standards, as a minimum to meet their obligations in their terms and conditions as a Standards User in the API Centre.
There are however a range of additional optional endpoints that API Providers can choose to support and provide if they decide to do so.
These endpoints have been defined as ‘mandatory’ and 'optional' in the specification for both the Account Information and Payments Initiation APIs.
The optional endpoints that are being made available will be published on the respective organisations' developer portals and made available upon request.
The intent of the API Centre and Standards Users is that no new optional functionalities will be introduced in future iterations of the API Specifications and that all currently optional functions will be phased out over time.