If you know the natonality of the spy you can confront their leader with demands. Put a spy in ALL your cities for counter-espionage. Give more EP weight to the offending civilization.
I would be nice to know exactly how your spies stop enemy spies. Do they help enemy spies get captured if they occupy the same tile or adjacent tiles etc.
What I was referring to is the spy unit claims that it "foils enemy spies" or something like that. I can't find any other mention of it in the Civlopedia, not even in the espionage section.
My question is where the spy needs to be, and what the effect is to "foil enemy spies."
This seems like a 3.13 change, because I don't remember the unit description of a spy saying anything like this before the patch.
Are you sure it's a specific spy saying that, and not just the random chance the spy is caught?
Where dioes it say having a static spy in a city does anything? I've heard people on the forum say it's doesn' do anything at all, only counterespionage and spy buildings...