ASP.NET MVC + WCF how to pass non-standard type?

Question

ASP.NET

There is a wcf service and asp.net mvc applications.
With the standard data type returned from the wcf service, asp.net mvc creates entries in the configuration file and knows about the class that represents this service.
But if I create a new data type in a separate assembly that is included in wcf and in asp.net mvc or return a Dictionary, there are no entries in the configuration and access to the service class on the client.
For some reason, in the tutorials, no one has such a problem, like here, for example , c-sharpcorner.com .
CHADNT?