Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: valentinabojan

packages/uipath-platform/src/uipath/platform/guardrails/_guardrails_service.py

@@ -121,10 +121,11 @@ def evaluate_guardrail(
             "parameters": parameters,
             "guardrailName": guardrail.name,
         }
-        if (
-            guardrail.validator_type == BYO_VALIDATOR_TYPE
-            and guardrail.byo_validator_name is not None
-        ):
+        if guardrail.validator_type == BYO_VALIDATOR_TYPE:
+            if not guardrail.byo_validator_name:
+                raise ValueError(
+                    "BYOG guardrails require byo_validator_name when validator_type is 'byo'."
+                )
             payload["byoValidatorName"] = guardrail.byo_validator_name
         spec = RequestSpec(
             method="POST",