People often add two things that can be really useful in a lot of contexts: explicit Acceptance Criteria and some kind of wireframe or mockup.
In other cases, the intent is clear enough, even without this stuff, for everyone to figure out what they need to figure out from the story: what should I do, am I done doing it, was this done right, etc.
Decide if it's enough by talking about it with the people who will need to figure out the answers to those questions while they're using the story.