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JavaScript@langchain/langgraph-sdkuiensureHistoryMessageInstances
Function●Since v1.7

ensureHistoryMessageInstances

Converts plain message objects within each history state's values to proper BaseMessage class instances. Returns a new array with shallow-copied states whose messages have been coerced.

Copy
ensureHistoryMessageInstances<
  StateType extends Record<string, unknown>
>(history: ThreadState<StateType>[], messagesKey: string = "messages"): ThreadState<StateType>[]

Parameters

NameTypeDescription
history*ThreadState<StateType>[]
messagesKeystring
Default:"messages"
View source on GitHub