I'm interested in the same thing, but there is very little content on the forum about experiences with Upwork API. Usually, there are questions on how to get API access and how API keys don't work, without a lot of detail afterward.
Looks like RSS/ATOM feed could also be used to make a custom feed, but again I can't find strictly what the rules and restrictions are for such a thing.
I would also like someone to share their experiences or Upwork representatives to share their tips and suggestions with us.