Though they may not officially boast that they are working for R&AW/CBI/indian intelligence agencies , it is very simple for an indian citizen to find out if a person is working or is associated with the indian intelligence agencies. For example on a forum, when a domain investor commented about the google, tata sponsored R&AW/CBI employees, other members said that they have got a” government job” indicating that the practice is fairly widespread. In another case, a relative was very surprised that a relatively mediocre housewife (stealing the identity of the domain investor), had got the job when she was only looking after her house and family.
The best way to check if a person is a intelligence employee is to ask the person directly on his or her face. Most of them are very surprised that the other person knows about it and they will not confirm or deny. It is worth capturing the expression on the face of the indian intelligence employee when asked the question. So though there is no official proof, it is simple to find the name, get a photo of the intelligence employee or file daily reports of their activities.