From an OCLC Announcement:
OCLC has launched the new WorldCat Metadata API that will enable member libraries and partners to build and share applications on the OCLC WorldShare Platform for libraries to catalog their collections in WorldCat.
The WorldCat Metadata API supports a variety of cataloging functionality for libraries to catalog their collections in WorldCat. Libraries will be able to create applications with the new API to add new and enrich existing WorldCat bibliographic records, and maintain WorldCat institution holdings and local bibliographic data.
The WorldCat Metadata API complements the WorldCat Search API. These Web services provide read and write access to libraries’ bibliographic and holdings data. A number of library- and partner-built applications already use the WorldCat Search API and have been well-received by the OCLC membership.
Read the Complete Announcement
Learn More From the OCLC Developer Network