ToolCall Class — langchain Architecture

Source Code

libs/core/langchain_core/messages/tool.py lines 206–239

class ToolCall(TypedDict):
    """Represents an AI's request to call a tool.

    Example:
        ```python
        {"name": "foo", "args": {"a": 1}, "id": "123"}
        ```

        This represents a request to call the tool named `'foo'` with arguments
        `{"a": 1}` and an identifier of `'123'`.

    !!! note "Factory function"

        `tool_call` may also be used as a factory to create a `ToolCall`. Benefits
        include:

        * Required arguments strictly validated at creation time
    """

    name: str
    """The name of the tool to be called."""

    args: dict[str, Any]
    """The arguments to the tool call as a dictionary."""

    id: str | None
    """An identifier associated with the tool call.

    An identifier is needed to associate a tool call request with a tool
    call result in events when multiple concurrent tool calls are made.
    """

    type: NotRequired[Literal["tool_call"]]
    """Used for discrimination."""