langchain_core.tracers.log_stream.LogStreamCallbackHandler

class langchain_core.tracers.log_stream.LogStreamCallbackHandler(*, auto_close: bool = True, include_names: Optional[Sequence[str]] = None, include_types: Optional[Sequence[str]] = None, include_tags: Optional[Sequence[str]] = None, exclude_names: Optional[Sequence[str]] = None, exclude_types: Optional[Sequence[str]] = None, exclude_tags: Optional[Sequence[str]] = None, _schema_format: Literal['original', 'streaming_events'] = 'streaming_events')

A tracer that streams run logs to a stream.

A tracer that streams run logs to a stream.

Parameters

• auto_close – Whether to close the stream when the root run finishes.

• include_names – Only include runs from Runnables with matching names.

• include_types – Only include runs from Runnables with matching types.

• include_tags – Only include runs from Runnables with matching tags.

• exclude_names – Exclude runs from Runnables with matching names.

• exclude_types – Exclude runs from Runnables with matching types.

• exclude_tags – Exclude runs from Runnables with matching tags.

• _schema_format –

  Primarily changes how the inputs and outputs are handled. For internal use only. This API will change. - ‘original’ is the format used by all current tracers.

  This format is slightly inconsistent with respect to inputs and outputs.

  • ’streaming_events’ is used for supporting streaming events,

    for internal usage. It will likely change in the future, or be deprecated entirely in favor of a dedicated async tracer for streaming events.

Attributes

ignore_agent	Whether to ignore agent callbacks.
ignore_chain	Whether to ignore chain callbacks.
ignore_chat_model	Whether to ignore chat model callbacks.
ignore_llm	Whether to ignore LLM callbacks.
ignore_retriever	Whether to ignore retriever callbacks.
ignore_retry	Whether to ignore retry callbacks.
raise_error
run_inline

Methods

__init__(*[, auto_close, include_names, ...])	A tracer that streams run logs to a stream.
include_run(run)
on_agent_action(action, *, run_id[, ...])	Run on agent action.
on_agent_finish(finish, *, run_id[, ...])	Run on agent end.
on_chain_end(outputs, *, run_id[, inputs])	End a trace for a chain run.
on_chain_error(error, *[, inputs])	Handle an error for a chain run.
on_chain_start(serialized, inputs, *, run_id)	Start a trace for a chain run.
on_chat_model_start(serialized, messages, *, ...)	Start a trace for an LLM run.
on_llm_end(response, *, run_id, **kwargs)	End a trace for an LLM run.
on_llm_error(error, *, run_id, **kwargs)	Handle an error for an LLM run.
on_llm_new_token(token, *[, chunk, ...])	Run on new LLM token.
on_llm_start(serialized, prompts, *, run_id)	Start a trace for an LLM run.
on_retriever_end(documents, *, run_id, **kwargs)	Run when Retriever ends running.
on_retriever_error(error, *, run_id, **kwargs)	Run when Retriever errors.
on_retriever_start(serialized, query, *, run_id)	Run when Retriever starts running.
on_retry(retry_state, *, run_id, **kwargs)	Run on a retry event.
on_text(text, *, run_id[, parent_run_id])	Run on arbitrary text.
on_tool_end(output, *, run_id, **kwargs)	End a trace for a tool run.
on_tool_error(error, *, run_id, **kwargs)	Handle an error for a tool run.
on_tool_start(serialized, input_str, *, run_id)	Start a trace for a tool run.
tap_output_aiter(run_id, output)	Tap an output async iterator to stream its values to the log.

__init__(*, auto_close: bool = True, include_names: Optional[Sequence[str]] = None, include_types: Optional[Sequence[str]] = None, include_tags: Optional[Sequence[str]] = None, exclude_names: Optional[Sequence[str]] = None, exclude_types: Optional[Sequence[str]] = None, exclude_tags: Optional[Sequence[str]] = None, _schema_format: Literal['original', 'streaming_events'] = 'streaming_events') → None

A tracer that streams run logs to a stream.

Parameters

• auto_close – Whether to close the stream when the root run finishes.

• include_names – Only include runs from Runnables with matching names.

• include_types – Only include runs from Runnables with matching types.

• include_tags – Only include runs from Runnables with matching tags.

• exclude_names – Exclude runs from Runnables with matching names.

• exclude_types – Exclude runs from Runnables with matching types.

• exclude_tags – Exclude runs from Runnables with matching tags.

• _schema_format –

  Primarily changes how the inputs and outputs are handled. For internal use only. This API will change. - ‘original’ is the format used by all current tracers.

  This format is slightly inconsistent with respect to inputs and outputs.

  • ’streaming_events’ is used for supporting streaming events,

    for internal usage. It will likely change in the future, or be deprecated entirely in favor of a dedicated async tracer for streaming events.

include_run(run: Run) → bool

on_agent_action(action: AgentAction, *, run_id: UUID, parent_run_id: Optional[UUID] = None, **kwargs: Any) → Any

Run on agent action.

on_agent_finish(finish: AgentFinish, *, run_id: UUID, parent_run_id: Optional[UUID] = None, **kwargs: Any) → Any

Run on agent end.

on_chain_end(outputs: Dict[str, Any], *, run_id: UUID, inputs: Optional[Dict[str, Any]] = None, **kwargs: Any) → Run

End a trace for a chain run.

on_chain_error(error: BaseException, *, inputs: Optional[Dict[str, Any]] = None, run_id: UUID, **kwargs: Any) → Run

Handle an error for a chain run.

on_chain_start(serialized: Dict[str, Any], inputs: Dict[str, Any], *, run_id: UUID, tags: Optional[List[str]] = None, parent_run_id: Optional[UUID] = None, metadata: Optional[Dict[str, Any]] = None, run_type: Optional[str] = None, name: Optional[str] = None, **kwargs: Any) → Run

Start a trace for a chain run.

on_chat_model_start(serialized: Dict[str, Any], messages: List[List[BaseMessage]], *, run_id: UUID, tags: Optional[List[str]] = None, parent_run_id: Optional[UUID] = None, metadata: Optional[Dict[str, Any]] = None, name: Optional[str] = None, **kwargs: Any) → Run

Start a trace for an LLM run.

on_llm_end(response: LLMResult, *, run_id: UUID, **kwargs: Any) → Run

End a trace for an LLM run.

on_llm_error(error: BaseException, *, run_id: UUID, **kwargs: Any) → Run

Handle an error for an LLM run.

on_llm_new_token(token: str, *, chunk: Optional[Union[GenerationChunk, ChatGenerationChunk]] = None, run_id: UUID, parent_run_id: Optional[UUID] = None, **kwargs: Any) → Run

Run on new LLM token. Only available when streaming is enabled.

on_llm_start(serialized: Dict[str, Any], prompts: List[str], *, run_id: UUID, tags: Optional[List[str]] = None, parent_run_id: Optional[UUID] = None, metadata: Optional[Dict[str, Any]] = None, name: Optional[str] = None, **kwargs: Any) → Run

Start a trace for an LLM run.

on_retriever_end(documents: Sequence[Document], *, run_id: UUID, **kwargs: Any) → Run

Run when Retriever ends running.

on_retriever_error(error: BaseException, *, run_id: UUID, **kwargs: Any) → Run

Run when Retriever errors.

on_retriever_start(serialized: Dict[str, Any], query: str, *, run_id: UUID, parent_run_id: Optional[UUID] = None, tags: Optional[List[str]] = None, metadata: Optional[Dict[str, Any]] = None, name: Optional[str] = None, **kwargs: Any) → Run

Run when Retriever starts running.

on_retry(retry_state: RetryCallState, *, run_id: UUID, **kwargs: Any) → Run

Run on a retry event.

on_text(text: str, *, run_id: UUID, parent_run_id: Optional[UUID] = None, **kwargs: Any) → Any

Run on arbitrary text.

on_tool_end(output: str, *, run_id: UUID, **kwargs: Any) → Run

End a trace for a tool run.

on_tool_error(error: BaseException, *, run_id: UUID, **kwargs: Any) → Run

Handle an error for a tool run.

on_tool_start(serialized: Dict[str, Any], input_str: str, *, run_id: UUID, tags: Optional[List[str]] = None, parent_run_id: Optional[UUID] = None, metadata: Optional[Dict[str, Any]] = None, name: Optional[str] = None, inputs: Optional[Dict[str, Any]] = None, **kwargs: Any) → Run

Start a trace for a tool run.

async tap_output_aiter(run_id: UUID, output: AsyncIterator[T]) → AsyncIterator[T]

Tap an output async iterator to stream its values to the log.