In section 3.4.4 of the CDS Services Spec page, it says both:

 For example, if a suggestion recommends substituting naproxen for acetaminophen, a create action may be used to apply a MedicationRequest for acetaminophen to the current order entry task.

and

• Substituting NSAID for acetaminophen – MedicationRequest for acetaminophen

But I think the general interpretation of "substituting naproxen for acetaminophen" is that the patient will be given naproxen rather than acetameinophen but your example seems the reverse. It think these should either say "substituting naproxen WITH acetaminophen" or "substituting acetaminophen for naproxen"