diff --git a/docs/ApiValidationRules.md b/docs/ApiValidationRules.md
index cffec3d..ec18ec9 100644
--- a/docs/ApiValidationRules.md
+++ b/docs/ApiValidationRules.md
@@ -65,18 +65,8 @@ If a validation rule fails the call should return 400 (Bad request) including an
 
 ```json
 {
-    "message" : "reason why this call failed",
-    "errors" : [ {"error_message" : "first error message",
-                   "error_description" : "first error description"},
-                 {"error_message" : "second error message",
-                  "error_description":"second error description"},
-                   ... ...
-               ],
-    "valid_data" : {
-        "key1" : "value 1",
-        "key2" : "value 2"
-        ... (data actually evaluated by the server)
-    }
+    "error_field" : "A reference to the respective field(s) which have caused the error",
+    "error_description" : "Reason why this call failed"
 }
 ```