diff --git a/lib/accounts/user.ex b/lib/accounts/user.ex
index b0d919b..655dcc6 100644
--- a/lib/accounts/user.ex
+++ b/lib/accounts/user.ex
@@ -361,6 +361,7 @@ defmodule Mv.Accounts.User do
     # 1:1 relationship - User belongs to a Role
     # This automatically creates a `role_id` attribute in the User table
     # The relationship is optional (allow_nil? true by default)
+    # Foreign key constraint: on_delete: :restrict (prevents deleting roles assigned to users)
     belongs_to :role, Mv.Authorization.Role
   end