diff --git a/schema/openapi.json b/schema/openapi.json
index 03adcf1..eb2cd88 100644
--- a/schema/openapi.json
+++ b/schema/openapi.json
@@ -833,7 +833,8 @@
             "type": "boolean",
             "description": "A Boolean value indicating if there is an empty result set"
           }
-        }
+        },
+        "required": ["empty"] 
       }
     },
     "parameters": {