The level of detail and nature of the information should be appropriate for the level of exposure of the service so as not to expose sensitive information to untrusted clients.
The format for error messages is described in [OData-Atom] and [OData-JSON].
This document describes the operation model for the protocol, specifying the interactions between clients and servers for retrieving and manipulating data in an OData service.
It builds on the [OData-Core] document for core concepts, [OData-URI] for URI conventions and on the formats specifications for Atom [OData-Atom] and JSON [OData-JSON] for the description of data representations.
Atom Pub also introduces service documents, with a content-type of "application/atomsvc xml".