init() — langchain Function Reference

Architecture documentation for the __init__() function in structured_output.py from the langchain codebase.

Function python LangChainCore Runnables

Entity Profile

LangChainCore→ Runnables→ __init__() — langchain Function Reference

Dependency Diagram

graph TD
  b0c9fec5_c27c_af1a_7146_cef231d28fa3["__init__()"]
  4ecead60_ac3b_7004_f7d6_8d475c41d81d["ToolStrategy"]
  b0c9fec5_c27c_af1a_7146_cef231d28fa3 -->|defined in| 4ecead60_ac3b_7004_f7d6_8d475c41d81d
  style b0c9fec5_c27c_af1a_7146_cef231d28fa3 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/langchain_v1/langchain/agents/structured_output.py lines 223–257

    def __init__(
        self,
        schema: type[SchemaT] | UnionType | dict[str, Any],
        *,
        tool_message_content: str | None = None,
        handle_errors: bool
        | str
        | type[Exception]
        | tuple[type[Exception], ...]
        | Callable[[Exception], str] = True,
    ) -> None:
        """Initialize `ToolStrategy`.

        Initialize `ToolStrategy` with schemas, tool message content, and error handling
        strategy.
        """
        self.schema = schema
        self.tool_message_content = tool_message_content
        self.handle_errors = handle_errors

        def _iter_variants(schema: Any) -> Iterable[Any]:
            """Yield leaf variants from Union and JSON Schema oneOf."""
            if get_origin(schema) in {UnionType, Union}:
                for arg in get_args(schema):
                    yield from _iter_variants(arg)
                return

            if isinstance(schema, dict) and "oneOf" in schema:
                for sub in schema.get("oneOf", []):
                    yield from _iter_variants(sub)
                return

            yield schema

        self.schema_specs = [_SchemaSpec(s) for s in _iter_variants(schema)]