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docs/Using-the-API/OAuth-details.md

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+We use the [Doorkeeper gem for OAuth](https://github.com/doorkeeper-gem/doorkeeper/wiki), so you can refer to their docs on specifics of the end-points.
+
+The API is divided up into access scopes:
+
+- `read`: Read data
+- `write`: Post statuses and upload media for statuses
+- `follow`: Follow, unfollow, block, unblock
+
+Multiple scopes can be requested during the authorization phase with the `scope` query param (space-separate the scopes).