diff --git a/README.md b/README.md
index 6ab4d417c..de7267908 100644
--- a/README.md
+++ b/README.md
@@ -119,6 +119,14 @@ This will load all the necessary scripts and make the Viewer accessible trough j
   })
   ```
 
+In order to open a shared file you will need to provide the share token
+so the Viewer can use it to authenticate the requests to the server.
+See the `files_sharing` app
+[controller](https://github.com/nextcloud/server/blob/master/apps/files_sharing/lib/Controller/ShareController.php#L404)
+and
+[template](https://github.com/nextcloud/server/blob/master/apps/files_sharing/templates/public.php#L18)
+for an example.
+
 ### Close the viewer
 ```js
 OCA.Viewer.close()