I wonder what the difference is between "operative", "agent" and just plain "employee". I see the media often refers to Rove as a political "operative".
As I recall, Novak used the term "operative" in his original column to describe Plame. He later stated (maybe in his follow-up column) that this is a general term that he uses and it was not meant to infer that Plame was a covert, undercover agent.
In CIA-talk "operative" could infer that she was employed by the "Operations" branch and those are the real spy-guys at the Agency. Since we know (or are at least fairly certain) that Plame was not working undercover at the CIA and had not been for quite some time, the MSM ranting about "outing a CIA undercover agent" is just so much baloney. They need to be called on it and called on it hard. They are using the old Clinton trick: just keep telling a lie over and over until it becomes the truth.
The terms probably have some formal definitions that aren't commonly adhered to. The general point is that CIA spooks don't work out of CIA HQ in Langley. People who drive in and out of that compound are known to be CIA employees, no way or reason to keep that fact covert.
Just Google "50 USC 426". This is the legal definition of "covert agent." "Operative" really has no meaning legally.