From 48c5596d83a02da6697d5d2f038bb5aa1ef2df54 Mon Sep 17 00:00:00 2001
From: PRABHU KIRAN VANDRANKI <72809214+VANDRANKI@users.noreply.github.com>
Date: Wed, 3 Jun 2026 16:37:59 -0400
Subject: [PATCH] fix: raise HTTPException(400) instead of
 CustomCodeExecutionError in apply_guardrail

Fixes #29436. When a custom code guardrail's execution fails (e.g. due to
a policy violation raised inside user-provided code), the except clause
wrapped the exception in CustomCodeExecutionError which is a plain Python
Exception with no HTTP status mapping. The proxy's error handler therefore
returned 500 instead of 400.

Raising HTTPException(status_code=400) directly keeps the same informative
error detail and is immediately handled by FastAPI, so the client receives
the correct 400 response code.
---
 .../custom_code/custom_code_guardrail.py               | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/litellm/proxy/guardrails/guardrail_hooks/custom_code/custom_code_guardrail.py b/litellm/proxy/guardrails/guardrail_hooks/custom_code/custom_code_guardrail.py
index 58502e309ef..afdd3630a55 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/custom_code/custom_code_guardrail.py
+++ b/litellm/proxy/guardrails/guardrail_hooks/custom_code/custom_code_guardrail.py
@@ -257,11 +257,11 @@ class CustomCodeGuardrail(CustomGuardrail):
             verbose_proxy_logger.error(
                 f"Custom code guardrail '{self.guardrail_name}' execution error: {e}"
             )
-            raise CustomCodeExecutionError(
-                f"Custom code guardrail execution failed: {e}",
-                details={
-                    "guardrail_name": self.guardrail_name,
-                    "input_type": input_type,
+            raise HTTPException(
+                status_code=400,
+                detail={
+                    "error": f"Custom code guardrail execution failed: {e}",
+                    "guardrail": self.guardrail_name,
                 },
             ) from e