diff --git a/util/config/schema.py b/util/config/schema.py
index 0f0fccaf5..1f66f5db1 100644
--- a/util/config/schema.py
+++ b/util/config/schema.py
@@ -353,7 +353,7 @@ CONFIG_SCHEMA = {
       'type': 'string',
       'description': 'The authentication engine to use for credential authentication.',
       'x-example': 'Database',
-      'enum': ['Database', 'LDAP', 'JWT', 'Keystone', 'OIDC'],
+      'enum': ['Database', 'LDAP', 'JWT', 'Keystone', 'OIDC', 'AppToken'],
     },
     'SUPER_USERS': {
       'type': 'array',