 <p>I was able to get this to work by adding my custom class to the Entity Framework model (even though it does not have a table). I think it was easier with the a code model. I don't know if it would have been doable with a design model (edmx).</p> <p>This link got me started:</p> <p><a href="http://breeze.github.io/doc-js/metadata-with-ef.html" rel="nofollow">http://breeze.github.io/doc-js/metadata-with-ef.html</a></p>