Rich Site Summary (RSS) and Atom services are not true web services. Instead, they are a family of web feed formats that allow sites to publish content updates in a standard format. Regardless of their proper classification, consumption of feed services is enabled in the Web Services panel.
Selecting Feed from the web service type selector simply prompts us to import the pre-built WaveMaker feed service into the project:
There is no further configuration to be performed in the Web Services tab after importing the feed service. The feed service is now part of the project services tree with two functions: