Add a model directly under a project

To add a model directly under a project, call the AddNewRootModel method of the IProject object.

public void AddRootModel(ICommandContext c, ICommandParams p) 
{ 
//Create a model of the metaclass "UseCaseModel" in the project 
IProject project = c.App.Workspace.CurrentProject; 
IModel ucModel = project.AddNewRootModel("UseCaseModel"); 

//... 
}