What did IDF chief of staff Kochavi mean when he spoke of an operation he "could not talk about"?

After intercepting the UAVs launched at the Shark rig and reports of the assassination of Hezbollah operatives in Syria, Kochavi referred to the operation that began last weekend.

He vaguely clarified: "Not everything we want to tell, and certainly I will not tell you everything either"

Source: Kan News