Is Dialyzer a Worthwhile Tool?

Dalyzer is a tool that runs first all types from the standard library and from anything you might be using. It then contracts out against the type annotations. I feel it is a worthwhile tool for anything which might be consumed by somebody else, like a library and it has a clearly defined API. You want to make sure that you give as much correct information as you can, but internally, I'm not so sure.