apidoc and swagger are two nice projects which are focusing on documentation of APIs. This project is a middle tier which tries to bring them together in a sense that it uses apidoc to convert inline documentation to json schema and later convert it to swagger json schmea.
http://apidocjs.com/#param-api-param
For example:
The default value shows up as 0 when generating swagger.json. When generating doc with api-doc, the default shows up as 18.