Commerce Foundation Metadata Extensibility Point
You can extend existing commerce entities simply by changing the properties and mapping information from the Metadata file or by adding new relationships. In order to add new relationships, you must add new server side code to the operation sequence.
You can introduce new commerce entities to metadata which will be discovered using the Microsoft Multi-Channel Commerce Foundation Metadata API. These new commerce entities may require server side code to be added.
See Also
Other Resources
Commerce Foundation Request and Response Extensibility Point