Idea: How should the advises relationship be constrained?

In AOP we have a uses and an advises relationship
between two aspectual components.

A class A may only use classes that are 
immediate part classes
classes of method arguments and
classes that are instantiated.

An AC A may only use
participant classes and their immediate part classes
classes of participant method arguments and
classes that are instantiated in AC.

What about the advises relationship? How should 
the advises relationship be constrained?

Johan would say that we can only advise something that declares
its willingness to be advised.

An AC also defines constraints that the advised classes
need to satisfy. How do we formulate those constraints?
Can we use Alloy? Advising for an AC is a collaborative 
activity and it is a collection of classes that needs to satisfy
certain rules for it to be advised.

-- Karl