The Superdesk Content API has been integrated into the Superdesk server core and can now be found at https://github.com/superdesk/superdesk-core/tree/master/content_api
The Superdesk Content API is a read-only API focused on delivering news content; news items and packages created, produced and published in Superdesk.
The Superdesk Content API is an open source project developed and maintained by Sourcefabric.
Check it out at http://docs.superdeskcontentapi.apiary.io/