Personally, I now consider that too long. I have built entire products using index cards with nothing more than 3-8 words on them, plus occasional temporary artifacts (whiteboard sketches, mocks, etc).

In my view, stories are tokens for conversation. Now when I deal with teams who are writing down more than a few words, I look for barriers to conversation. E.g., not all the right people sitting together, or too much work in process.