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JavaScript@langchain/coretracerslog_streamLogStreamCallbackHandlerhandleChatModelStart

Method●Since v1.0

handleChatModelStart

Copy

handleChatModelStart(
  llm: Serialized,
  messages: BaseMessage<MessageStructure<MessageToolSet>, MessageType>[

View source on GitHub

]

[

]

,

runId

:

string

,

parentRunId

:

string

,

extraParams

:

,

tags

:

string

[

]

,

metadata

:

,

name

:

string

)

:

<

>

Parameters

Name	Type	Description
`llm`*	`Serialized`
`messages`*	`BaseMessage<MessageStructure<MessageToolSet>, MessageType>[][]`
`runId`*	`string`
`parentRunId`	`string`
`extraParams`	`KVMap`
`tags`	`string[]`
`metadata`	`KVMap`
`name`	`string`

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