Where can I find: REST Proxy, a good best practice document and does/don'ts?

I'm building a REST api for our web services, this is going to be used both internally and externally so I want it to be as standard as possible.

As this is the first time I'm using REST in ExtJS I would like to find a best practice document and also some does and don'ts. I've noticed ExtJS kind of expects the responses to be formed in a particular way.

For instance when creating an object I'm just returning the new ID, but ExtJS wants the whole new object to be returned. It seams to work with just the ID though, but I'm not sure it's the correct way.

Any guidance is highly appreciated!

Where can I find: REST Proxy, a good best practice document and does/don'ts?