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_on_chain_start() — langchain Function Reference

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

Function python Observability Tracers called by 2

Entity Profile

Dependency Diagram

graph TD
  0983c53e_c9c4_70ff_cd08_6f356740fd06["_on_chain_start()"]
  b3ab8001_c14c_4191_ca53_2dbabc99917f["AsyncBaseTracer"]
  0983c53e_c9c4_70ff_cd08_6f356740fd06 -->|defined in| b3ab8001_c14c_4191_ca53_2dbabc99917f
  9d98e4df_1dff_cdb6_b489_397648f5aa8a["on_chain_start()"]
  9d98e4df_1dff_cdb6_b489_397648f5aa8a -->|calls| 0983c53e_c9c4_70ff_cd08_6f356740fd06
  4fc30b16_7ae1_9cd3_3e1a_cab2c2a53122["on_chain_start()"]
  4fc30b16_7ae1_9cd3_3e1a_cab2c2a53122 -->|calls| 0983c53e_c9c4_70ff_cd08_6f356740fd06
  style 0983c53e_c9c4_70ff_cd08_6f356740fd06 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/core/langchain_core/tracers/base.py lines 890–891

    async def _on_chain_start(self, run: Run) -> None:
        """Process the Chain Run upon start."""

Domain

Subdomains

Defined In

Called By

Source

Frequently Asked Questions

What does _on_chain_start() do?
_on_chain_start() is a function in the langchain codebase, defined in libs/core/langchain_core/tracers/base.py.
Where is _on_chain_start() defined?
_on_chain_start() is defined in libs/core/langchain_core/tracers/base.py at line 890.
What calls _on_chain_start()?
_on_chain_start() is called by 2 function(s): on_chain_start, on_chain_start.

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