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Pythonlangchain-coreutilsutilsLC_ID_PREFIX

Attribute●Since v1.0

LC_ID_PREFIX

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LC_ID_PREFIX = 'lc_run-'

View source on GitHub

Internal tracing/callback system identifier.

Used for:

Tracing. Every LangChain operation (LLM call, chain execution, tool use, etc.) gets a unique run_id (UUID)
Enables tracking parent-child relationships between operations