Web Services?

Dear Schema folks,

In the W3C Web Annotation Working Group, we have defined a (simple, RESTy,
JSON-LD based) protocol [1] for interactions between clients and servers.
We would love to have a way to discover those services, from web pages and
indeed any web resource.

Our current approach is to have a link header from any resource to the URL
of the service, however if we could align with any existing approaches in
the broader schema.org community, this seems valuable. In trawling for the
appropriate classes and predicates, the closest seems to be ServiceChannel,
however it /has/ a serviceUrl, rather than being the service that is
identified by the URL.

The relationship we're looking for is: (some web resource) has_service (web
service URL)
Along the lines of:
    http://example.org/diagram.jpg has_service
http://example.org/services/annotations/
That could be added in a link header, <link> element, or in a JSON-LD
description of the resource.

Any advice would be appreciated :)

Thanks,

Rob Sanderson

[1] Draft: http://w3c.github.io/web-annotation/protocol/wd/

-- 
Rob Sanderson
Information Standards Advocate
Digital Library Systems and Services
Stanford, CA 94305