
Resolves YES if one country attacks another country with a nuclear weapon for reasons that are clearly a part of the Russia-Ukraine conflict. Resolves NO if the conflict is resolved without any such detonations.
A "resolved" confict means that we reach a state of affairs where it doesn't seem likely that one country will use force against another any time in the near future. They don't have to actually be friendly with each other, but there do need to be no threatening troop movements or nonviolent attacks such as government-sponsored hacks or aggressive economic sanctions.
A nuclear test meant to intimidate an opposing country doesn't count.
@Guilhermesampaiodeoliveir somebody bought a chunk of YES this morning, presumably because they believe that Ukraine's recent drone attack (which took out a bunch of Russian strategic bombers, ie nuclear launch capability) paradoxically gives Russia more incentive to nuke Ukraine before more of their arsenal is compromised. Looks like the market doesn't agree with them, though.
Also see https://manifold.markets/ChristopherKing/russia-coupnuke-combination-market?r=Q2hyaXN0b3BoZXJLaW5n