diff --git a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2018-01-01-preview/authorization-RoleBasedCalls.json b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2018-01-01-preview/authorization-RoleBasedCalls.json
index 007b8c3c32aa..4651046b3edc 100644
--- a/specification/authorization/resource-manager/Microsoft.Authorization/preview/2018-01-01-preview/authorization-RoleBasedCalls.json
+++ b/specification/authorization/resource-manager/Microsoft.Authorization/preview/2018-01-01-preview/authorization-RoleBasedCalls.json
@@ -971,6 +971,10 @@
         "roleName": {
           "type": "string",
           "description": "Returns role definition with the specific name."
+        },
+        "type": {
+          "type": "string",
+          "description": "Returns role definition with the specific type."
         }
       },
       "description": "Role Definitions filter"