Before they delved into debate over scaling back bond purchases at their December meeting, Federal Reserve officials peered further into the future — discussing the experimental bond-trading program that could one day become the lever the central bank uses to set short-term interest rates.

The New York Fed, at the policy-making committee’s direction, has been testing the program since September. Known as a “reverse repo” facility, all operations of the tool “to date had proceeded smoothly,” staff reported during the meeting, according to minutes released Wednesday.