Explicitly recommend not commentingIf you can't say anything nice, don't say anything at all.

YouExplicitly recommend sayingnot commenting. People on the internet don't always seem to understand that that's a very good option. A good time to exercise this option is when the OP is wrong and you feel very strongly about that. Another time is when you fail to come up with a constructive response. Saying nice things instead of saying mean things it's great, but those mean things areit's also longer, more thoughtfulharder, and possibly less cathartic than just gettingit's not practical for a flippant comment off one's chest. Explicitly instruct not commenting even whenlot of people a lot of the OPtime because constructive, kind human interaction is wronggenuinely difficult, holdsbut it's much easier if we can actually choose the situations where we want to be kind and constructive. If I were enforcing a "be kind" clause in a code of conduct, I would feel on far better footing to point out to an opinion you disagree withoffender that they didn't have to say anything at all, and so forththe burden is not on the moderator or the platform to make sure it's always possible for them to say something nice. 

I think yourthe code of conduct is really incomplete without explicitly highlighting that.

Relatedly, use shorter examples for alternate nice comments. We want something feasible, not something saintlycommenting is an active expectation we have alongside our active expectation for those who comment to comment constructively.