BerriAI/litellm · error · LassoGuardrailAPIError

API error: {error.response.status_code}

Error message

API error: {error.response.status_code}

What it means

Catch-all LassoGuardrailAPIError for any Lasso API HTTP error other than 401 and 429 — httpx raised HTTPStatusError and the status code fell through the specific branches. The message embeds the raw status code (e.g. 'API error: 503'), which is the key diagnostic.

Source

Thrown at litellm/proxy/guardrails/guardrail_hooks/lasso/lasso.py:618

            error,
            extra={
                "guardrail_name": getattr(self, "guardrail_name", "unknown"),
                "message_type": message_type,
                "error_type": type(error).__name__,
            },
        )

        # Handle specific error types if httpx is available
        if HTTPX_AVAILABLE:
            if isinstance(error, httpx.TimeoutException):
                raise LassoGuardrailAPIError("Lasso API timeout")
            elif isinstance(error, httpx.HTTPStatusError):
                if error.response.status_code == 401:
                    raise LassoGuardrailMissingSecrets("Invalid API key")
                elif error.response.status_code == 429:
                    raise LassoGuardrailAPIError("Lasso API rate limit exceeded")
                else:
                    raise LassoGuardrailAPIError(f"API error: {error.response.status_code}")

        # Generic error handling
        raise LassoGuardrailAPIError(f"Failed to verify request safety with Lasso API: {error}")

    def _log_masking_applied(
        self,
        message_type: Literal["PROMPT", "COMPLETION"],
        response: dict[str, Any],
    ) -> None:
        """Log masking application with structured context."""
        conversation_id: Final = getattr(self, "conversation_id", "unknown")
        verbose_proxy_logger.debug(
            "Lasso masking applied",
            extra={
                "guardrail_name": getattr(self, "guardrail_name", "unknown"),
                "message_type": message_type,
                "violations_count": len(response.get("findings", {})),
                "masked_fields": len(response.get("messages", [])),

View on GitHub (pinned to 77b7c6c40c)

Solutions

1. Read the status code from the message and the Lasso response details in the preceding log line, then act on that specific status.
2. For 5xx, check the Lasso status page and retry later — these are server-side and transient in most cases.
3. For 403/404, verify the guardrail's api_base/endpoint configuration and that your key's plan permits the API being called.
4. For 400/413, reduce or reshape the payload, and upgrade litellm if the request schema changed between versions.

from litellm.proxy.guardrails.guardrail_hooks.lasso.lasso import LassoGuardrailAPIError
import re

def lasso_status_code(err: Exception) -> int | None:
    """Extract the HTTP status embedded in 'API error: <code>' messages."""
    if isinstance(err, LassoGuardrailAPIError):
        m = re.search(r"API error: (\d{3})", str(err))
        if m:
            return int(m.group(1))
    return None

from litellm.proxy.guardrails.guardrail_hooks.lasso.lasso import LassoGuardrailAPIError

try:
    result = await guardrail_hook(data)
except LassoGuardrailAPIError as e:
    code = lasso_status_code(e)
    if code and 500 <= code < 600:
        # Lasso-side incident: circuit-break, then degrade per your policy
        trip_lasso_circuit_breaker(cooldown_s=60)
        raise
    raise  # 4xx (other than 401/429) = config/payload problem — fix, don't retry

When it happens

Trigger: The guardrail's call to the Lasso API returns an error status other than 401/429: 400 for a malformed/unsupported payload, 403 for permission or plan restrictions, 404 for a wrong api_base/endpoint, 413 for oversized payloads, or 5xx during a Lasso-side incident.

Common situations: Lasso 5xx outages or maintenance windows; a litellm version change sending a request shape the deployed Lasso endpoint rejects; a customized/wrong api_base in the guardrail config; extremely large prompts tripping 413.

Understand the failure class

Background: "API error: {status}" and "HTTP 401/403/404/429/5xx" errors: non-2xx HTTP responses explained — this error's family across 27 libraries.

Related errors

• error_message
• Lasso API timeout
• Invalid API key
• Lasso API rate limit exceeded
• Failed to verify request safety with Lasso API: {error}

AI-assisted analysis of BerriAI/litellm@77b7c6c40c (2026-08-18). Data as JSON: /api/errors/e7ebaaf5eda2d239. Report an issue: GitHub.