2.2.6.4.1 EDMSimpleType Property

By default, the raw value (identified via URIs with resource paths ending in "$value") of any EDMSimpleType property (except those of type Edm.Binary) SHOULD be represented using the text/plain media type and MUST be serialized as specified in Common Serialization Rules for XML-based Formats (section 2.2.6.1). A $value request for a property that is NULL SHOULD result in a "404 Not Found" response. A data service MAY<64> customize the media type used for any property. The raw value of an Edm.Binary property MUST be an unencoded byte stream.

If the value of the property to be serialized is null, see Common Serialization Rules for XML-based Formats (section 2.2.6.1), because the representation is format specific.