Communist Manifesto—that's a pretty straightforward—and now infamous—title. Check: it's a manifesto, a document publicly announcing the author's goals and the reasons behind those goals. Check: it's written by a communist.
More specifically, the secretive Communist League asked Karl Marx to write this baby in order to make their goals public to European (and any other) workers, since uprisings seemed about to happen on the continent. At one point, the League even sent Karl a message telling him to hurry up with it, which may be why it ends kind of abruptly.
So, yeah, the Communist Manifesto is pretty much a communist manifesto.