I think they would look at level of organization and society, Like our ability to actually imagine the inner world of an insect is pretty close to zero but we have a very good idea of which species have a very high level of sociality and organization, and which are essentially mute loners.

I love octopuses with all of my being, but most species are almost completely solitary—for some mating involves ripping off their member and chucking it across the inky blue at their coparent. Even for colony forming octopuses the level of social interaction is fairly low like they don’t really take care of each others young or feed each other and they only live a few years each so forming a diplomatic relationship would be hard.