Does my code have to be well-formed?

No, no and no. We’re all for standards and clean code, but this is a special case. Aside from the open source mandate, your entry can be sloppy. The beauty of open sources is that truly innovative and creative apps will very likely generate a community of developers on their own. It just needs to work well enough to demonstrate the proof of concept and persuade the community to get involved. We are after creative and new ways to present information.