During the past years, the data deluge that prevails in the World Wide Web has been accompanied by a number of APIs that expose business logic. In this paper, we discuss a novel approach to enrich existing API standards definitions with business rules. Taking advantage of the REST principles, we aim at enabling the creation of generic clients that can dynamically navigate through semantically enriched web affordances with the help of Hydrabased Hypermedia API descriptions, which encapsulate the finite state machine of possible actions into SWRL rules.