According to Polymarket, “A prediction market on whether Russia will use nuclear weapons has been requested many times”.
It detailed that “this market will resolve to ‘Yes’ if the Russian Federation detonates a nuclear device in an offensive capacity by Dec. 31, 2022, 11:59:59 p.m. ET.
Otherwise, market will resolve to ‘No.’” Also, to meet the "yes" criterion, the detonation of a nuclear weapon must be an offensive capability, not a test.