diff --git a/services/admin-api.md b/services/admin-api.md
index 7b317b57..de0c3901 100644
--- a/services/admin-api.md
+++ b/services/admin-api.md
@@ -152,9 +152,16 @@ does not by itself support translation.
 
 ## Tags
 
-- `created-by-<vm>`
-- `managed-by-<vm>`
-- `backup-<id>`
+*not implemented yet*
+
+The tags provided can be used to write custom policies. They are not used in
+a&nbsp;default Qubes OS installation. However, they are created anyway.
+
+- `created-by-<vm>` &emdash;&nbsp;Created in an extension to qubesd at the
+  moment of creation of the VM. Cannot be changed via API, which is also
+  enforced by this extension.
+- `managed-by-<vm>` &emdash;&nbsp;Can be used for the same purpose, but it is
+  not created automatically, nor is it forbidden to set or reset this tag.
 
 ## General notes