Abstract
Optional
input: BaseCallbackHandlerInputAbstract
nameOptional
handleCalled when an agent is about to execute an action, with the action and the run ID.
Optional
parentRunId: stringOptional
tags: string[]Optional
handleCalled when an agent finishes execution, before it exits. with the final output and the run ID.
Optional
parentRunId: stringOptional
tags: string[]Optional
handleCalled at the end of a Chain run, with the outputs and the run ID.
Optional
parentRunId: stringOptional
tags: string[]Optional
kwargs: { Optional
inputs?: Record<string, unknown>Optional
handleOptional
handleCalled at the start of a Chain run, with the chain name and inputs and the run ID.
Optional
parentRunId: stringOptional
tags: string[]Optional
metadata: Record<string, unknown>Optional
runType: stringOptional
name: stringOptional
handleCalled at the start of a Chat Model run, with the prompt(s) and the run ID.
Optional
parentRunId: stringOptional
extraParams: Record<string, unknown>Optional
tags: string[]Optional
metadata: Record<string, unknown>Optional
name: stringOptional
handleLLMEndCalled at the end of an LLM/ChatModel run, with the output and the run ID.
Optional
parentRunId: stringOptional
tags: string[]Optional
handleLLMErrorOptional
handleLLMNewCalled when an LLM/ChatModel in streaming
mode produces a new token
idx.prompt is the index of the prompt that produced the token (if there are multiple prompts) idx.completion is the index of the completion that produced the token (if multiple completions per prompt are requested)
Optional
parentRunId: stringOptional
tags: string[]Optional
fields: HandleLLMNewTokenCallbackFieldsOptional
handleLLMStartCalled at the start of an LLM or Chat Model run, with the prompt(s) and the run ID.
Optional
parentRunId: stringOptional
extraParams: Record<string, unknown>Optional
tags: string[]Optional
metadata: Record<string, unknown>Optional
name: stringOptional
handleOptional
parentRunId: stringOptional
tags: string[]Optional
handleOptional
handleOptional
parentRunId: stringOptional
tags: string[]Optional
metadata: Record<string, unknown>Optional
name: stringOptional
handleOptional
handleOptional
handleOptional
handleCalled at the start of a Tool run, with the tool name and input and the run ID.
Optional
parentRunId: stringOptional
tags: string[]Optional
metadata: Record<string, unknown>Optional
name: stringStatic
from
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.