I'm building a REST service that will host multiple controllers (microservices). As a whole, lets call the service "Bob". So swagger displays "Bob" / "A collection of Bob Microservices". Then the controller names are listed. Right now, it just shows XYZ, ABC, etc. Is there a way to maybe have swagger show "XYZ - A collection of XYZ APIs" or something of that sort?

Seems like swagger shows the ///Summary on the methods, but not on the controllers.

Is there a way to maybe have swagger show "XYZ - A collection of XYZ APIs"

Yes. Here is one of the easiest ways. The ASP.NET Core version of Swagger leverages the ApiExplorerSettings attribute. You can set the GroupName.

public class BobController 
{
    [ApiExplorerSettings(GroupName="XYZ - A collection of XYZ APIs")]
    public IActionResult MyAction() 
    {
        ...
    }
}

The group name appears in the Swagger UI with the group's actions listed as operations underneath.

Edit: Here is an idea based on SledgeHammer's comment.

Swagger ASP.NET Core uses an IApiDescriptionGroupCollectionProvider to build its description groups. We could implement our own, using the default ApiDescriptionGroupCollectionProvider for inspiration, and register our provider during Startup.ConfigureServices. Our implementation would make the ApiDescriptionGroups() method return the GroupName associated with each action's controller. Then we could put the ApiExplorerSettings attribute on each controller instead of onto each action.