fix(guardrails): return HTTP 400 instead of 500 for guardrail-blocked requests

GuardrailRaisedException had no status_code attribute, so the generic
exception handler in _handle_llm_api_exception() defaulted to 500.

Guardrail blocks are client errors (the request content violated policy),
not server errors. Add status_code=400 to GuardrailRaisedException so
the proxy returns the correct HTTP status.

litellm/exceptions.py

@@ -917,10 +917,12 @@ class GuardrailRaisedException(Exception):
         guardrail_name: Optional[str] = None,
         message: str = "",
         should_wrap_with_default_message: bool = True,
+        status_code: int = 400,
     ):
         default_message = f"Guardrail raised an exception, Guardrail: {guardrail_name}, Message: {message}"
         self.guardrail_name = guardrail_name
         self.message = default_message if should_wrap_with_default_message else message
+        self.status_code = status_code
         super().__init__(self.message)
 
 

tests/test_litellm/proxy/guardrails/guardrail_hooks/test_generic_guardrail_api.py

@@ -553,6 +553,8 @@ class TestGuardrailActions:
             # Verify the exception has the clean error message (no wrapper)
             assert str(exc_info.value) == "Content contains harmful instructions"
             assert exc_info.value.guardrail_name == "generic_guardrail_api"
+            # Guardrail blocks should map to 400, not 500
+            assert exc_info.value.status_code == 400
 
     @pytest.mark.asyncio
     async def test_action_intervened_modifies_content(