_on_chat_model_start() — langchain Function Reference

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

Function python Observability Tracers calls 1 called by 1

Entity Profile

Observability→ Tracers→ _on_chat_model_start() — langchain Function Reference

Dependency Diagram

graph TD
  1f28ee91_49f8_e93f_e967_a9380e8e96a7["_on_chat_model_start()"]
  178590bb_85ff_b79e_979a_46e5c3c5389f["LangChainTracer"]
  1f28ee91_49f8_e93f_e967_a9380e8e96a7 -->|defined in| 178590bb_85ff_b79e_979a_46e5c3c5389f
  68b325b2_a4ee_6bd3_7e65_01239a5c497c["on_chat_model_start()"]
  68b325b2_a4ee_6bd3_7e65_01239a5c497c -->|calls| 1f28ee91_49f8_e93f_e967_a9380e8e96a7
  cf43defe_cb35_deb4_9782_55f973cdf6ca["_persist_run_single()"]
  1f28ee91_49f8_e93f_e967_a9380e8e96a7 -->|calls| cf43defe_cb35_deb4_9782_55f973cdf6ca
  style 1f28ee91_49f8_e93f_e967_a9380e8e96a7 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/core/langchain_core/tracers/langchain.py lines 296–300

    def _on_chat_model_start(self, run: Run) -> None:
        """Persist an LLM run."""
        if run.parent_run_id is None:
            run.reference_example_id = self.example_id
        self._persist_run_single(run)