Getting back to the OP:
Imagine this:
A player looks at an object of indescript material, location, and size.
The player decides they want to break the object. Do you let them do so? And how do you do it? ...
As per instruction, I'm imagining:
DM (after a dice roll): The room in which you find yourself contains a vase.
Player: I smash the vase on the floor.
Now, from the player's perspective, this is "an object of indescript material, location, and size" but solely because descriptions of the "material, location, and size" have not been given. Those are things for the DM to know and, if relevant, to present.
... What is the limit? Does it depend on context or as long as the object doesn't say its unbreakable, they can break it?
Yeah, it depends on the context, of any and perhaps all of the things mentioned and perhaps other things such as the composition of the floor. Maybe you need to decide whether the vase is made of poor-quality pottery or adamantium and whether the floor is laid with swathes of wool (perhaps there's a reason you didn't mention it) or is lined with bricks.
I'd think that the Rule of Cool along with Rules as Fun could apply to situations like this. If there hasn't been something specified that you want to follow, make something up.
If, in a future encounter, they want to better predict the possible outcome of an action, they should ask questions first.