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JavaScript@langchain/corecallbacksbaseBaseCallbackHandlerhandleLLMStart

Method●Since v1.0

handleLLMStart

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handleLLMStart(
  llm: Serialized,
  prompts: string[],
  runId: string,
  parentRunId: string,
  extraParams:

View source on GitHub

<

string

,

unknown

>

,

tags

:

string

[

]

,

metadata

:

<

string

,

unknown

>

,

runName

:

string

)

:

any

Parameters

Name	Type	Description
`llm`*	`Serialized`
`prompts`*	`string[]`
`runId`*	`string`
`parentRunId`	`string`
`extraParams`	`Record<string, unknown>`
`tags`	`string[]`
`metadata`	`Record<string, unknown>`
`runName`	`string`

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