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Universal Hub Node Load Serializable Encoder Backed File System In Memory

Agents Caches Base Dispatch Web Manager Promises Chat History Context Base Langsmith Documents Embeddings Errors Example Selectors Indexing Base Chat Models Llms Profile Load Serializable Memory Messages Tool Output Parsers Openai Functions Openai Tools Outputs Prompt Values Prompts Retrievers Document Compressors Runnables Graph Singletons Stores Structured Query Tools Base Console Log Stream Run Collector Tracer Langchain Stream Async Caller Chunk Array Context Env Event Source Parse Format Function Calling Hash Json Patch Json Schema Math Ssrf Stream Testing Tiktoken Types Vectorstores

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JavaScript@langchain/coremessagesisFunctionMessage

Function●Since v1.0

isFunctionMessage

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isFunctionMessage(x: BaseMessage): x is FunctionMessage<MessageStructure<MessageToolSet>>

Parameters

Name	Type	Description
`x`*	`BaseMessage`

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