diff --git a/output/schema/validation-errors.json b/output/schema/validation-errors.json
index 6470f235cb..f6fab219e8 100644
--- a/output/schema/validation-errors.json
+++ b/output/schema/validation-errors.json
@@ -1,11 +1,4 @@
 {
-  "endpointErrors": {
-    "esql.async_query_get": {
-      "request": [
-        "Request: query parameter 'format' does not exist in the json spec"
-      ],
-      "response": []
-    }
-  },
+  "endpointErrors": {},
   "generalErrors": []
 }
\ No newline at end of file
diff --git a/specification/_json_spec/esql.async_query_get.json b/specification/_json_spec/esql.async_query_get.json
index b2b4b17ccc..f92bce11c9 100644
--- a/specification/_json_spec/esql.async_query_get.json
+++ b/specification/_json_spec/esql.async_query_get.json
@@ -24,6 +24,10 @@
       ]
     },
     "params": {
+      "format": {
+        "type": "string",
+        "description": "a short version of the Accept header, e.g. json, yaml"
+      },
       "wait_for_completion_timeout": {
         "type": "time",
         "description": "Specify the time that the request should block waiting for the final response"