Personally, I like a very basic summary, like 1-2 sentences about what the character or characters do in the fic. The summary doesn't necessarily have to refer to the tropes, as that's what tags are for.

I'm not usually a fan of snippet summaries because then you have to read the same paragraph twice, which seems redundant.

And I definitely don't like summaries that are like "What will happen when X?" They give you a good idea of the maturity of the writing.