# This file was auto-generated by Fern from our API Definition.

import typing_extensions
from ..core.serialization import FieldMetadata


class SplitClassificationParams(typing_extensions.TypedDict):
    """
    A classification for document splitting. Extends the base Classification with an optional `identifierKey` field for per-type identifier extraction rules.
    """

    id: str
    """
    Unique identifier for the classification. We recommend lowercase, underscore-separated format.
    """

    type: str
    """
    Type identifier for the classification.
    """

    description: str
    """
    A detailed description of the classification.
    """

    identifier_key: typing_extensions.NotRequired[
        typing_extensions.Annotated[str, FieldMetadata(alias="identifierKey")]
    ]
    """
    A natural-language rule describing how to extract a unique identifier for subdocuments of this type. For example, `"Extract the invoice number from the document header"`.
    
    When provided, the splitter will extract the specified identifier for each subdocument of this type and include it in the output as the `identifier` field. This enables merging of related subdocuments that share the same extracted identifier.
    
    **Availability:** Supported on `splitting_light` >= 1.3.0 and `splitting_performance` >= 1.5.0. If provided on older versions, this field is accepted but ignored.
    """
