Create a new Rule called “Events”:

Evil Operations are Events.
Spotting an Agent is an Event.

The Henchman who resolves an Event is the Resolver.
Each Henchman that participated in an Event (by following the rules of participation stated in that event’s definition) is a Participant.

Add to the stat listing under Rule “Weapons”:

Boons: A list of numerical modifiers and their asociated attributes. Whenever a Henchman joins an Event, if that event requires that Henchman’s attributes to be calculated, the henchman shall apply each of the modifiers from er weapon’s boon stat to their respective attributes, but only for the purpose of calculating those values (that is, no change is made to er GNDT attributes). Whenever an Event is resolved, if the resolver is required to caluculate the attributes of the Participants, for each Participant, the Resolver shall apply that Participant’s boon modifiers from any weapon e is using, but only for the purpose of calculating those values (that is, no change is made to the Participant’s GNDT attributes). If any of the items in the Boons list is not an attribute modifier, it is ignored. Modifiers shall always be applied from left to right.

Right now this version allows modifiers on joining and resolving, but does not allow any other actions tacked on to a weapon’s effects. If people want that, it should be a separate weapon stat.