pydantic/pydantic · error · PydanticUserError

invalid-annotated-type

invalid-annotated-type

Error message

'{annotation}' cannot annotate '{annotated_type}'.

What it means

Error "'{annotation}' cannot annotate '{annotated_type}'." thrown in pydantic/pydantic.

Source

Thrown at pydantic/types.py:2234

                kibit, mibit, gibit, tibit, pibit, eibit (bit units).

        Returns:
            The byte size in the new unit.
        """
        try:
            unit_div = self.byte_sizes[unit.lower()]
        except KeyError:
            raise PydanticCustomError('byte_size_unit', 'Could not interpret byte unit: {unit}', {'unit': unit})

        return self / unit_div


# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DATE TYPES ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


def _check_annotated_type(annotated_type: str, expected_type: str, annotation: str) -> None:
    if annotated_type != expected_type:
        raise PydanticUserError(f"'{annotation}' cannot annotate '{annotated_type}'.", code='invalid-annotated-type')


if TYPE_CHECKING:
    PastDate = Annotated[date, ...]
    FutureDate = Annotated[date, ...]
else:

    class PastDate:
        """A date in the past."""

        @classmethod
        def __get_pydantic_core_schema__(
            cls, source: type[Any], handler: GetCoreSchemaHandler
        ) -> core_schema.CoreSchema:
            if cls is source:
                # used directly as a type
                return core_schema.date_schema(now_op='past')
            else:

View on GitHub (pinned to 2e5f0e2b42)

When it happens

Trigger: Thrown at pydantic/types.py:2234 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of pydantic/pydantic@2e5f0e2b42 (2026-08-04). Data as JSON: /data/errors/989c113154e1a625.json. Report an issue: GitHub.