I don’t know about the CIA but this side of the pond Mi6 employs “Intelligence Officers” and “Field Agents” who run “Assets” who are often specialists assigned to particular operations. Even a Lock Smith could be on the books. Henry Paul, the Chauffeur of the Mercedes carrying Dodi and Diana in Paris the night they were killed (Assassinated) was an Mi6 Asset. He was the Head of Security and the Consierge at the Paris Ritz. He was being paid by British Intelligence to “Spy” on any Person or Persons of Interest using the Hotel or its facilities. Any decent Intelligence Agency will have permanent assets in all the top hotels all around the world. They are there to report on the comings and going’s of Foreign Diplomats, Politicians, High Profile Businessmen, Organised Crime Figures, Royalty, Celebrities, Terrorists and even enemy spies. There’s also a couple of very shady and secretive units of the SAS called “The Increment” and “The Clinic.” These highly skilled and experienced special forces units are the guys that carry out “Black Ops” such as assassinations, and other deniable missions. The SAS are professionals and use whatever weapons and equipment they require for the task at hand. So if a pocket knife or a paintball gun loaded with marbles is the most suitable tool then that’s what they will be issued. If the equipment needs to be untraceable then that’s not out of the capabilities of the Secret Intelligence Services of most countries. That’s not to say that they don’t have their favourite weapons. Intelligence Officers and Field Agents are a bit like Organ Grinders and their Assets are more like the Performing Monkeys.
Canada, Australia, New Zealand, the United Kingdom and the United States are known as “the 5 Eyes Alliance.” It is illegal for most intelligence agencies like the CIA or Mi6 to spy on their own citizens. They get around this by getting a secret service agency from a friendly foreign country to spy on their own citizens for them. There are agencies like the FBI or Mi5 who can investigate their citizens and have jurisdiction in their own country but they are limited by the laws of the land. Unlike foreign agents and agencies who are operating covertly and are not subject to the same restrictions by their governments.