SA-REST is a simple and open microformat for enhancing Web resources with additional semantic information. In addition to HTML and XHTML, the SA-REST approach can also be used to enrich Atom, RSS, and arbitrary XML. SA-REST is one of several open microformat standards.
SA-REST is a microformat to add additional meta-data to (but not limited to) REST API descriptions in HTML and XHTML. Developers can directly embed meta-data from various models such an ontology, taxonomy or a tag cloud into their API descriptions. The embedded meta-data can be used to improve search (for example: perform faceted search for APIs), data mediation (in conjunction with XML annotation) as well as help in easier integration of services to create mashups.
SA-REST submission to W3C can be found here: http://www.w3.org/Submission/SA-REST/
More information about SA-REST can be found here: http://wiki.knoesis.org/index.php/SA-REST