BerriAI/litellm · error · ValueError

sensitive_data_route_to_model must be set when on_sensitive_

Error message

sensitive_data_route_to_model must be set when on_sensitive_data='route'

What it means

Pydantic model_validator on guardrail params: on_sensitive_data was set to 'route' but sensitive_data_route_to_model was left unset, so the router has no destination model to send flagged requests to.

Source

Thrown at litellm/types/guardrails.py:962

        "on_disallowed_action",
        "unreachable_fallback",
        "on_sensitive_data",
        mode="before",
        check_fields=False,
    )
    @classmethod
    def normalize_lowercase(cls, v):
        """Normalize string and list fields to lowercase for ALL guardrail types."""
        if isinstance(v, str):
            return v.lower()
        if isinstance(v, list):
            return [x.lower() if isinstance(x, str) else x for x in v]
        return v

    @model_validator(mode="after")
    def validate_sensitive_data_routing(self) -> "BaseLitellmParams":
        if self.on_sensitive_data == "route" and not self.sensitive_data_route_to_model:
            raise ValueError("sensitive_data_route_to_model must be set when on_sensitive_data='route'")
        return self

    model_config = ConfigDict(extra="allow", protected_namespaces=())


class Mode(BaseModel):
    tags: dict[str, str | list[str]] = Field(description="Tags for the guardrail mode")
    default: str | list[str] | None = Field(default=None, description="Default mode when no tags match")


class LitellmParams(
    CiscoAIDefenseGuardrailConfigModel,
    PresidioConfigModel,
    BedrockGuardrailConfigModel,
    LakeraV2GuardrailConfigModel,
    HeadroomGuardrailConfigModel,
    CompresrGuardrailConfigModel,
    RepelloAIGuardrailConfigModel,

View on GitHub (pinned to 77b7c6c40c)

Solutions

1. Set sensitive_data_route_to_model to the target model when on_sensitive_data='route'.
2. Or change on_sensitive_data to 'block'/'mask' if routing is not needed.

When it happens

Trigger: Thrown at litellm/types/guardrails.py:962 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of BerriAI/litellm@77b7c6c40c (2026-08-18). Data as JSON: /api/errors/fc282e887f758ea6. Report an issue: GitHub.