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_CallableReturningSystemMessage Class — langchain Architecture

Architecture documentation for the _CallableReturningSystemMessage class in types.py from the langchain codebase.

Class python

Entity Profile

Dependency Diagram

graph TD
  074456b8_5fac_fa96_009a_e55fd3070831["_CallableReturningSystemMessage"]
  fb1284e2_76fc_661f_c16d_e084e8c2b175["types.py"]
  074456b8_5fac_fa96_009a_e55fd3070831 -->|defined in| fb1284e2_76fc_661f_c16d_e084e8c2b175
  7a043b3a_b93c_f4c4_4e35_e01151390930["__call__()"]
  074456b8_5fac_fa96_009a_e55fd3070831 -->|method| 7a043b3a_b93c_f4c4_4e35_e01151390930

Relationship Graph

Source Code

libs/langchain_v1/langchain/agents/middleware/types.py lines 811–818

class _CallableReturningSystemMessage(Protocol[StateT_contra, ContextT]):  # type: ignore[misc]
    """Callable that returns a prompt string or SystemMessage given `ModelRequest`."""

    def __call__(
        self, request: ModelRequest[ContextT]
    ) -> str | SystemMessage | Awaitable[str | SystemMessage]:
        """Generate a system prompt string or SystemMessage based on the request."""
        ...

Defined In

Source

Frequently Asked Questions

What is the _CallableReturningSystemMessage class?
_CallableReturningSystemMessage is a class in the langchain codebase, defined in libs/langchain_v1/langchain/agents/middleware/types.py.
Where is _CallableReturningSystemMessage defined?
_CallableReturningSystemMessage is defined in libs/langchain_v1/langchain/agents/middleware/types.py at line 811.

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