LangChain Reference home pageLangChain ReferenceLangChain Reference
  • GitHub
  • Main Docs
Deep Agents
LangChain
LangGraph
Integrations
LangSmith
  • Overview
    • Overview
    • Caches
    • Callbacks
    • Documents
    • Document loaders
    • Embeddings
    • Exceptions
    • Language models
    • Serialization
    • Output parsers
    • Prompts
    • Rate limiters
    • Retrievers
    • Runnables
    • Utilities
    • Vector stores
    MCP Adapters
    Standard Tests
    Text Splitters
    ⌘I

    LangChain Assistant

    Ask a question to get started

    Enter to send•Shift+Enter new line

    Menu

    OverviewCachesCallbacksDocumentsDocument loadersEmbeddingsExceptionsLanguage modelsSerializationOutput parsersPromptsRate limitersRetrieversRunnablesUtilitiesVector stores
    MCP Adapters
    Standard Tests
    Text Splitters
    Language
    Theme
    Pythonlangchain-coretracerscontext
    Module●Since v0.1

    context

    Context management for tracers.

    Attributes

    attribute
    tracing_callback_var: Any
    attribute
    tracing_v2_callback_var: ContextVar[LangChainTracer | None]
    attribute
    run_collector_var: ContextVar[RunCollectorCallbackHandler | None]

    Functions

    function
    tracing_v2_enabled

    Instruct LangChain to log all runs in context to LangSmith.

    function
    collect_runs

    Collect all run traces in context.

    function
    register_configure_hook

    Register a configure hook.

    Classes

    class
    LangChainTracer

    Implementation of the SharedTracer that POSTS to the LangChain endpoint.

    class
    RunCollectorCallbackHandler

    Tracer that collects all nested runs in a list.

    This tracer is useful for inspection and evaluation purposes.

    class
    BaseCallbackHandler

    Base callback handler.

    class
    AsyncCallbackManager

    Async callback manager that handles callbacks from LangChain.

    class
    CallbackManager

    Callback manager for LangChain.

    Type Aliases

    typeAlias
    Callbacks: list[BaseCallbackHandler] | BaseCallbackManager | None
    View source on GitHub