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Agents Caches Base Dispatch Web Manager Promises Chat History Context Base Langsmith Documents Embeddings Errors Example Selectors Indexing Base Chat Models Compat Event Llms Openai Completions Stream Profile Stream Structured Output Load Serializable Memory Messages Tool Output Parsers Openai Functions Openai Tools Outputs Prompt Values Prompts Retrievers Document Compressors Runnables Graph Singletons Stores Structured Query Testing 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 Standard Schema Stream Testing Tiktoken Types Uuid Vectorstores

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JavaScript@langchain/corepromptsBasePromptTemplatemetadata

Property●Since v0.3

metadata

Metadata to be used for tracing.

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metadata: Record<string, unknown>

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