Abstract base class for creating callback handlers in the LangChain framework. It provides a set of optional methods that can be overridden in derived classes to handle various events during the execution of a LangChain application.

Hierarchy (view full)

Constructors

Properties

awaitHandlers: boolean = ...
ignoreAgent: boolean = false
ignoreChain: boolean = false
ignoreCustomEvent: boolean = false
ignoreLLM: boolean = false
ignoreRetriever: boolean = false
name: string = "single_run_extractor"

The name of the callback handler.

raiseError: boolean = false
runPromise: Promise<Run>
runPromiseResolver: ((run: Run) => void)
runMap: Map<string, Run> = ...

Methods

  • Called at the end of a Chain run, with the outputs and the run ID.

    Parameters

    • outputs: ChainValues
    • runId: string
    • Optional_parentRunId: string
    • Optional_tags: string[]
    • Optionalkwargs: {
          inputs?: Record<string, unknown>;
      }
      • Optionalinputs?: Record<string, unknown>

    Returns Promise<Run>

  • Called if a Chain run encounters an error

    Parameters

    • error: unknown
    • runId: string
    • Optional_parentRunId: string
    • Optional_tags: string[]
    • Optionalkwargs: {
          inputs?: Record<string, unknown>;
      }
      • Optionalinputs?: Record<string, unknown>

    Returns Promise<Run>

  • Called at the start of a Chain run, with the chain name and inputs and the run ID.

    Parameters

    • chain: Serialized
    • inputs: ChainValues
    • runId: string
    • OptionalparentRunId: string
    • Optionaltags: string[]
    • Optionalmetadata: KVMap
    • OptionalrunType: string
    • Optionalname: string

    Returns Promise<Run>

  • Called at the start of a Chat Model run, with the prompt(s) and the run ID.

    Parameters

    • llm: Serialized
    • messages: BaseMessage[][]
    • runId: string
    • OptionalparentRunId: string
    • OptionalextraParams: KVMap
    • Optionaltags: string[]
    • Optionalmetadata: KVMap
    • Optionalname: string

    Returns Promise<Run>

  • Called at the start of an LLM or Chat Model run, with the prompt(s) and the run ID.

    Parameters

    • llm: Serialized
    • prompts: string[]
    • runId: string
    • OptionalparentRunId: string
    • OptionalextraParams: KVMap
    • Optionaltags: string[]
    • Optionalmetadata: KVMap
    • Optionalname: string

    Returns Promise<Run>

  • Called at the start of a Tool run, with the tool name and input and the run ID.

    Parameters

    • tool: Serialized
    • input: string
    • runId: string
    • OptionalparentRunId: string
    • Optionaltags: string[]
    • Optionalmetadata: KVMap
    • Optionalname: string

    Returns Promise<Run>