diff --git a/src/bentoml/_internal/monitoring/default.py b/src/bentoml/_internal/monitoring/default.py
index e8ed6054cf..d29da282bc 100644
--- a/src/bentoml/_internal/monitoring/default.py
+++ b/src/bentoml/_internal/monitoring/default.py
@@ -45,7 +45,8 @@
 formatters:
   bentoml_json:
     class: pythonjsonlogger.jsonlogger.JsonFormatter
-    format: " "
+    format: "()"
+    validate: false
 """