litellm - 💡(How to fix) Fix [Bug]: generic_guardrail_api blocks logged as guardrail_failed_to_respond instead of guardrail_intervened [1 pull requests]

@staticmethod
def _is_guardrail_intervention(e: Exception) -> bool:
    if isinstance(e, ModifyResponseException):
        return True
    if (HTTPException is not None
        and isinstance(e, HTTPException)
        and e.status_code == 400):
        return True
    return False

---

from litellm.exceptions import GuardrailRaisedException

@staticmethod
def _is_guardrail_intervention(e: Exception) -> bool:
    if isinstance(e, GuardrailRaisedException):
        return True
    if isinstance(e, ModifyResponseException):
        return True
    if (HTTPException is not None
        and isinstance(e, HTTPException)
        and e.status_code == 400):
        return True
    return False

---

## Log Output

### Adapter log (block detected correctly)


{
  "_msg": "scan complete",
  "_time": "2026-05-18T13:36:31.139946872Z",
  "log.is_valid": "false",
  "log.level": "INFO",
  "log.msg": "scan complete",
  "log.scanners.PromptInjection": "1"
}


### LiteLLM log (misclassified as error, returns 500)


13:36:31 - LiteLLM Proxy:ERROR: utils.py:5611 - Exception: blocked by: PromptInjection (score: 1.00)
Traceback (most recent call last):
  File ".../proxy/guardrails/guardrail_endpoints.py", line 2233, in apply_guardrail
    guardrailed_inputs = await active_guardrail.apply_guardrail(...)
  File ".../integrations/custom_guardrail.py", line 958, in async_wrapper
    return self._process_error(e=e, ...)
  File ".../integrations/custom_guardrail.py", line 788, in _process_error
    raise e
  File ".../integrations/custom_guardrail.py", line 943, in async_wrapper
    response = await func(*args, **kwargs)
  File ".../proxy/guardrails/guardrail_hooks/generic_guardrail_api/generic_guardrail_api.py", line 481, in apply_guardrail
    raise GuardrailRaisedException(...)
litellm.exceptions.GuardrailRaisedException: blocked by: PromptInjection (score: 1.00)

INFO: 10.244.4.4:39408 - "POST /guardrails/apply_guardrail HTTP/1.1" 500 Internal Server Error


Note: The adapter correctly returns `{"action": "BLOCKED", "blocked_reason": "blocked by: PromptInjection (score: 1.00)"}` with HTTP 200. LiteLLM's `generic_guardrail_api.py` correctly raises `GuardrailRaisedException`. But `_process_error` classifies it as `guardrail_failed_to_respond` because `_is_guardrail_intervention` doesn't check for `GuardrailRaisedException`.