From the shell, you can embed API calls in select statements. This allows you to experiment with operations before adding them to calls from your code. The shell lets you build collections, add items, and experiment with CRUD operations. Other operations apply filters and support queries, as well as building indexes across one or more fields in a collection. You can find a lengthy list of documented API functions in the project wiki, grouped into common sets of operations.

For now, the GitHub wiki is the main source of documentation for DocumentDB. It’s a little on the thin side and could do with more examples. However, DocumentDB is currently intended for developers who want an alternative to MongoDB, one that’s available with an open source license rather than a source-available license. For now, as there’s no SDK, you’ll need to build your own calls to the API. These are based on MongoDB, so porting applications shouldn’t be too complex.

Why this? Why now?

The reasoning behind the DocumentDB project seems to be the big ambition to deliver a standard NoSQL API and engine, much like that developed for SQL. Microsoft has a lot of experience working in standards bodies, especially building and delivering the essential tests needed to make sure that any implementation of the resulting standard meets the necessary requirements.