With the Google Custom Search PHP SDK by Google, developers can interact the API to access search and customization features. It contains authentication with Api Key and authorization with OAuth 2.0. Examples demonstrate how to build the client object, build the service object, call an API, and handle the result.
Innovation in web service APIs is not always technical, sometimes it's about money. Such is the case with Yahoo's announcement that later this year they will begin charging for usage of BOSS (Build your Own Search Service), their search web service for developers. Given that search revenue is typically ad-driven, and that advertising doesn't typically mesh with APIs, this has meant that search APIs have been one of the most challenging classes of APIs for providers to monetize. So it's notable to see how Yahoo has chosen to tackle this: via a 'utility' pricing model, somewhat akin to how infrastructure services like Amazon Web Services charge by usage.
EBSCO announced that Sweden's Stockholm University has selected the EBSCO Discovery Service (EDS) which includes custom integration of the EDS API into the institution's library software platform. The University was looking for a reliable search and discovery solution that would be easy to integrate with the existing library software platform.