Diceless just means you play the story out through story telling without using numbers and dice to determine the outcome.
That's not quite true.
Taken most literally, diceless just means that it doesn't involve dice. Diceless games may or may not involve other randomizers, and they generally involve some sort of numbers. Everway, for example, involves no dice, but it does use a tarot-like deck, and characters have numeric traits.
Sometimes people say diceless when they mean randomless. Randomless games involve no chance, but they often involve numbers and resource management. Nobilis has four numerical traits and each has a pool of miracle points. You don't succeed or fail based on chance, but on how willing you are to spend your resources, and how clever you are in bringing any conflict into an area in which you dominate.
What you've described above I would call freeform. The closest I can get from my game experience is Puppetland. Characters are defined by what they are (tall, strong, etc), what they can do (run very fast, climb moderately well, etc), and what they cannot do (fit through small spaces, shout loudly, etc). Players state their intention, and the GM tells them what happens.
A note on freeform RPGs: They often involve sharing narrative authority around the table to a degree not seen in "traditional" RPGs. I cannot recall the name of the game, but in one if your character is, for example, a knowledgeable biologist, you get the narrative authority to resolve any situation related to biological science information.
