It can be very helpful to import an web service or REST interface definition as a model. Then you can use the classes like this Import xml and JSon with MDriven

MDriven Designer can't import an XSD och WDSL directly.

Sparx on the other hand can import schemas and export to XMI, which in turn can be imported by MDriven Designer.

Importing XSD with Sparx

Using Sparx, edit and clean up the imported model. Usually you will want to remove all "elements", keeping on the classes

When ready, export the model using XML UML 2.4.1 and XMI 2.4.2.

Note! MDriven ONLY supports XMI 2.4.2