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    Pythonlangchain-corecallbacksbase
    Module●Since v0.1

    base

    Base callback handler for LangChain.

    Classes

    Type Aliases

    View source on GitHub
    class
    AgentAction
    class
    AgentFinish
    class
    Document
    class
    BaseMessage
    class
    ChatGenerationChunk
    class
    GenerationChunk
    class
    LLMResult
    class
    RetrieverManagerMixin
    class
    LLMManagerMixin
    class
    ChainManagerMixin
    class
    ToolManagerMixin
    class
    CallbackManagerMixin
    class
    RunManagerMixin
    class
    BaseCallbackHandler
    class
    AsyncCallbackHandler
    class
    BaseCallbackManager
    typeAlias
    Callbacks: list[BaseCallbackHandler] | BaseCallbackManager | None

    Represents a request to execute an action by an agent.

    The action consists of the name of the tool to execute and the input to pass to the tool. The log is used to pass along extra information about the action.

    Final return value of an ActionAgent.

    Agents return an AgentFinish when they have reached a stopping condition.

    Class for storing a piece of text and associated metadata.

    Note

    Document is for retrieval workflows, not chat I/O. For sending text to an LLM in a conversation, use message types from langchain.messages.

    Base abstract message class.

    Messages are the inputs and outputs of a chat model.

    Examples include HumanMessage, AIMessage, and SystemMessage.

    ChatGeneration chunk.

    ChatGeneration chunks can be concatenated with other ChatGeneration chunks.

    GenerationChunk, which can be concatenated with other Generation chunks.

    A container for results of an LLM call.

    Both chat models and LLMs generate an LLMResult object. This object contains the generated outputs and any additional information that the model provider wants to return.

    Mixin for Retriever callbacks.

    Mixin for LLM callbacks.

    Mixin for chain callbacks.

    Mixin for tool callbacks.

    Mixin for callback manager.

    Mixin for run manager.

    Base callback handler.

    Base async callback handler.

    Base callback manager.