We’ve recently made some updates to the REST API which is available here on WordPress.com and for any Jetpack-enabled site that has the REST API module activated. The API now has full read and write support for custom post types and post metadata.

You can specify a post’s post type when you create or edit it. If you’re fetching a single post, you will receive its post type in the response. Of course, you can also specify a post type when fetching a series of posts. In all cases the parameter to use or look out for is type.

You can also query posts by metadata using the new meta_key and meta_value parameters. You can add, update, delete or retrieve a post’s metadata when creating, editing or getting a single post, using the new metadata parameter which accepts an array of metadata keys, ids, previous_value