I mean, if someone says "I smash the vase," I don't think the "how" really matters, does it? They probably didn't specify because they assumed, as would I as the DM, that smashing a vase is a relatively self-explanatory action - does it really matter if they throw it on the ground or hit it with their sword? (If it did matter - like maybe throwing it on the floor could trigger a trap - then I would respond with "Okay, you definitely smash smash that thing! Describe how, exactly." In other words, no take-backsies!).
Generally, if I ask "how?" it implies that this is a non-trivial task and I want to know what the plan is so I can figure out if there needs to be a DC, consequences, etc.