Is there a way to display all the available services that the application exposes via Web Api actions? For example when a user goes to http://someurl/api/ he will get a list of all the available services, their descriptions and the required parameters? I remember that I've seen this once but I cannot find any documentation for it/
Refer following URL
http://www.asp.net/web-api/overview/getting-started-with-aspnet-web-api/creating-api-help-pages
you can also customize the help page as per your requirement.