BerriAI/litellm · error · ValueError

Parameter {k} is not supported for model {model}. Supported

Error message

Parameter {k} is not supported for model {model}. Supported parameters are {supported_params}. Set drop_params=True to drop unsupported parameters.

What it means

Error "Parameter {k} is not supported for model {model}. Supported parameters are {supported_params}. Set drop_params=True to drop unsupported parameters." thrown in BerriAI/litellm.

Source

Thrown at litellm/llms/fal_ai/image_generation/flux_pro_v11_ultra_transformation.py:85

                if k in supported_params:
                    # Use mapped parameter name if exists
                    mapped_key = param_mapping.get(k, k)
                    mapped_value = non_default_params[k]

                    # Transform specific parameters
                    if k == "response_format":
                        # Map OpenAI response formats to image formats
                        if mapped_value in ["b64_json", "url"]:
                            mapped_value = "jpeg"
                    elif k == "size":
                        # Map OpenAI size format to Flux aspect ratio
                        mapped_value = self._map_aspect_ratio(mapped_value)

                    optional_params[mapped_key] = mapped_value
                elif drop_params:
                    pass
                else:
                    raise ValueError(
                        f"Parameter {k} is not supported for model {model}. Supported parameters are {supported_params}. Set drop_params=True to drop unsupported parameters."
                    )

        return optional_params

    def _map_aspect_ratio(self, size: str) -> str:
        """
        Map OpenAI size format to Flux Pro aspect ratio format.

        OpenAI format: "1024x1024", "1792x1024", etc.
        Flux format: "21:9", "16:9", "4:3", "3:2", "1:1", "2:3", "3:4", "9:16", "9:21"

        Default: "16:9"
        """
        # Map common OpenAI sizes to Flux aspect ratios
        size_to_aspect_ratio: Final = {
            "1024x1024": "1:1",
            "512x512": "1:1",

View on GitHub (pinned to 6c2dcb801b)

Solutions

1. Remove the unsupported parameter or set drop_params=True.

When it happens

Trigger: Thrown at litellm/llms/fal_ai/image_generation/flux_pro_v11_ultra_transformation.py:85 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of BerriAI/litellm@6c2dcb801b (2026-08-15). Data as JSON: /api/errors/ab027054a46a9618. Report an issue: GitHub.