Integrated Library Systems often lack open APIs or existing services are difficult to reuse because of access restrictions, complexity, and poor documentations. This also applies to patron information, such as loans, reservations, and fees. After reviewing standards such as NCIP, SLNP, and the DLF-ILS recommendations, the Patrons Account Information API (PAIA) was specifed at the Common Library Network (GBV) .
PAIA consists of a small set of precisely defined access methods to look up patron information including fees, to renew and request documents, and to cancel requests. With PAIA it should be possible to make use of all patron methods that can be access in OPAC interfaces, also in third party applications, such as mobile Apps and discovery interfaces. The specification is divided into core methods and methods for authentification. This design will facilitate migration from insecure username/password authentification to more flexible systems based on OAuth 2.0. OAuth is also used by major service providers such as Google, Twitter, and Facebook.
The current draft of PAIA is available at http://gbv.github.com/paia/ and comments are welcome. The specification is hosted in a git repository, accompanied by a wiki. Both can be accessed publicly to correct and improve the specification until its final release.
PAIA complements the Document Availability Information API (DAIA)  which was created to access current availability information about documents in libraries and related institutions. Both PAIA and DAIA are being designed with a mapping to RDF, to also publish library information as linked data.