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prefactor_langchain.metadata_extractor module

prefactor_langchain.metadata_extractor module

Section titled “prefactor_langchain.metadata_extractor module”

Utilities for extracting metadata from LangChain objects.

prefactor_langchain.metadata_extractor.extract_error_info(error: Exception) → ErrorInfo

Section titled “prefactor_langchain.metadata_extractor.extract_error_info(error: Exception) → ErrorInfo”

Extract error information from an exception.

  • Parameters: error – The exception to extract information from.
  • Returns: ErrorInfo containing error details.

prefactor_langchain.metadata_extractor.extract_token_usage(response: Any) → TokenUsage | None

Section titled “prefactor_langchain.metadata_extractor.extract_token_usage(response: Any) → TokenUsage | None”

Extract token usage from a ModelResponse.

Checks each message in response.result for usage_metadata (the standard LangChain field populated by all providers), accumulating totals across messages.

  • Parameters: response – A ModelResponse object from LangChain.
  • Returns: TokenUsage if available, None otherwise.