CouchDB as the Restful API layer?

I am about to build a web application that shares resources through a Restful API.

It struck me that CouchDB already has a good Restful API layer.

So why would I create my own one.

Couldn't I just let other web applications use my resources (json documents) on CouchDB through it's Restful API directly instead of node.js being the middleman?

Or will I need some logic in between CouchDB and 3rd party web applications?

Haven't yet used CouchDB so I don't know if it's capable of handling advanced authorization and if the "design document javascript" applications are as good as "node.js javascript".