The Rackspace Billing API supports the JSON data serialization format.
The request format is specified by using the
Content-Type header and is required for operations that have a request body.
The response format can be specified in requests by using the
Accept header. A response can be serialized using a format that is different from the request. If no response format is specified, JSON is the default.
Some operations support an Atom representation that can be used to efficiently determine when the state of services has changed.