Open API Specification is a machine and human readable way to describe APIs. From these specs we can generate documentation, create libraries, and ensure that our users know exactly what to expect from our APIs. This talk shows you around OAS from the beginning, showing how to create the specs and recommending some tools to help the process. Once you have the spec, things get interesting and this talk will showcase some of the things that you can offer once your API is described in this way. This session is recommended for writers looking to become more API-savvy and API engineers wanting to make their APIs more useful to their users.