Can anyone recommend guidelines for high-level documentation of Web services?
This is the documentation that should allow someone with no knowledge about a particular Web service to come away with a basic understanding of its reason for being, its roadmap and examples of its usage.
Such documentation should fit onto two printed sides of A4/Letter paper and take someone less than 10 minutes to read.
Note that this is supplemental to the low-level API documentation that a developer would use to consume the interface.