@thejadmaster: Whatever the rules were, use of the "tragedy" tag (as delineated from "drama") was never completely consistent in practice on Batoto (which is the source of these tags of course) from what I've seen.
Proper tragedies (i.e. tales that end horribly) usually got the tag of course, but so would some works where a central tragedy formed the emotional core of the work, regardless of the nature of the conclusion (that is to say, such tags have been given before the conclusion is even -known-).
Of course, people didn't always abide by the rules in using tags on Batoto anyway...
What is clear, however, is it wasn't just because a work contained something tragic (e.g. death of a protagonist) at some point. At a bare minimum, it has to be fairly core to what the work is, to merit the tag.