call() — langchain Function Reference

Architecture documentation for the __call__() function in types.py from the langchain codebase.

Function python LangChainCore Runnables

Entity Profile

LangChainCore→ Runnables→ __call__() — langchain Function Reference

Dependency Diagram

graph TD
  9dbeaf19_90d5_e340_3752_e2f64ee061a6["__call__()"]
  94bc2397_fb60_d26c_5f02_b8b6f43ca816["_CallableReturningSystemMessage"]
  9dbeaf19_90d5_e340_3752_e2f64ee061a6 -->|defined in| 94bc2397_fb60_d26c_5f02_b8b6f43ca816
  style 9dbeaf19_90d5_e340_3752_e2f64ee061a6 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/langchain_v1/langchain/agents/middleware/types.py lines 814–818

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