FirstMiddleware Class — langchain Architecture

Architecture documentation for the FirstMiddleware class in test_wrap_model_call.py from the langchain codebase.

Class python

Entity Profile

Dependency Diagram

graph TD
  f0a84c26_4b73_9b7e_1030_6e71606c6bbe["FirstMiddleware"]
  949c7cf4_56fe_f3b4_cd89_9631a7e9cb1e["AgentMiddleware"]
  f0a84c26_4b73_9b7e_1030_6e71606c6bbe -->|extends| 949c7cf4_56fe_f3b4_cd89_9631a7e9cb1e
  573473e5_eb93_a7d7_84ba_c975071c09af["test_wrap_model_call.py"]
  f0a84c26_4b73_9b7e_1030_6e71606c6bbe -->|defined in| 573473e5_eb93_a7d7_84ba_c975071c09af
  07fd99e0_d84b_aa20_331d_083c04ac33fb["wrap_model_call()"]
  f0a84c26_4b73_9b7e_1030_6e71606c6bbe -->|method| 07fd99e0_d84b_aa20_331d_083c04ac33fb

Relationship Graph

Source Code

libs/langchain_v1/tests/unit_tests/agents/middleware/core/test_wrap_model_call.py lines 724–733

        class FirstMiddleware(AgentMiddleware):
            def wrap_model_call(
                self,
                request: ModelRequest,
                handler: Callable[[ModelRequest], ModelResponse],
            ) -> ModelCallResult:
                execution_order.append("first-before")
                response = handler(request)
                execution_order.append("first-after")
                return response