The Ten Essentials for Good API Documentation · An A List Apart Article
alistapart.com/article/the-ten-essentials-for-good-api-documentation
What Jamie wrote
Well thought through article thinking about the ten things you should make sure that you do when you publish an API. This is often an overlooked component. The team finishes the service and the last thing to go is to put the API documentation together. Sadly, bad docs and lack of understanding will dramatically impact the adoption of your API!