maybe some combination of visual representation with text. For example it's not easy to come up intuitive with names of operations which could be applied to some surface. But if you could say something like 'select top side of cylinder' and it will show you some possible names of operations (with illustrations/animations) which could be applied to it then it's easy to say back what it need to do without actually knowing what actually possible. So as result it maybe just much quicker way to interact with CAD that we are using currently.