Freebase, in announcing the closure of Freebase in December 2014, promised that a Knowledge Graph API would be made available as replacement for the Freebase API and widget. The Freebase API and widget will remain available for three months after a replacement for the Freebase Suggest Widget, still in development, is launched.
The API also allows users to get a “a ranked list of the most notable entities that match certain criteria.” This is conveyed as a numeric value for the
resultScore. The description of
resultScore merely states that “[r]esults with higher resultScores are considered better matches.”
resultScore and another new property with a range (expected type) of
detailedDescription, are all new extensions residing at the subdomain schema.googleapis.com. As far as I know this is the first external schema.org extension employed by Google.
UPDATE (23 December 2015) – Here are some quick initial observations on the API that I’ve made via the Semantic Search Marketing community on Google+: