Apologies if this is a duplicate, but GitHub search returns hundreds of results for anything relating to blocks and APIs.

Given that most blocks are defined client-side in React, I don't believe there's currently a means of exposing the available blocks via an API outside of the context of the Gutenberg editor.

I would like to see, for example, a REST API endpoint which exposes all the available blocks and their attributes for a given post ID or post type. This would open up the possibility of programatic management of blocks within a post via an external editor.