microsoft/autogen · error · ValueError

Expected 'data' key in the dictionary

Error message

Expected 'data' key in the dictionary

What it means

Error "Expected 'data' key in the dictionary" thrown in microsoft/autogen.

Source

Thrown at python/packages/autogen-core/src/autogen_core/_image.py:92

        return f'<img src="{self.data_uri}"/>'

    @property
    def data_uri(self) -> str:
        return _convert_base64_to_data_uri(self.to_base64())

    # Returns openai.types.chat.ChatCompletionContentPartImageParam, which is a TypedDict
    # We don't use the explicit type annotation so that we can avoid a dependency on the OpenAI Python SDK in this package.
    def to_openai_format(self, detail: Literal["auto", "low", "high"] = "auto") -> Dict[str, Any]:
        return {"type": "image_url", "image_url": {"url": self.data_uri, "detail": detail}}

    @classmethod
    def __get_pydantic_core_schema__(cls, source_type: Any, handler: GetCoreSchemaHandler) -> core_schema.CoreSchema:
        # Custom validation
        def validate(value: Any, validation_info: ValidationInfo) -> Image:
            if isinstance(value, dict):
                base_64 = cast(str | None, value.get("data"))  # type: ignore
                if base_64 is None:
                    raise ValueError("Expected 'data' key in the dictionary")
                return cls.from_base64(base_64)
            elif isinstance(value, cls):
                return value
            else:
                raise TypeError(f"Expected dict or {cls.__name__} instance, got {type(value)}")

        # Custom serialization
        def serialize(value: Image) -> dict[str, Any]:
            return {"data": value.to_base64()}

        return core_schema.with_info_after_validator_function(
            validate,
            core_schema.any_schema(),  # Accept any type; adjust if needed
            serialization=core_schema.plain_serializer_function_ser_schema(serialize),
        )


def _convert_base64_to_data_uri(base64_image: str) -> str:

View on GitHub (pinned to 027ecf0a37)

Solutions

1. Include the image bytes under the 'data' key

Example fix

{'data': <bytes>, ...} when constructing the image

When it happens

Trigger: Thrown at python/packages/autogen-core/src/autogen_core/_image.py:92 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of microsoft/autogen@027ecf0a37 (2026-08-15). Data as JSON: /api/errors/e21e3eb5a35f2ed2. Report an issue: GitHub.