Module @langfuse/vercel-ai-sdk

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@langfuse/vercel-ai-sdk

This package provides a Langfuse-owned telemetry integration for AI SDK v7 (ai@7) using the new callback-based telemetry system.

It emits AI SDK-compatible OpenTelemetry spans so it works with the existing Langfuse OTEL ingestion pipeline, and it adds Langfuse-specific trace and prompt attributes for user/session/tag/prompt linking.

Usage

import { generateText } from "ai";
import { createLangfuseTelemetry } from "@langfuse/vercel-ai-sdk";

await generateText({
  model,
  prompt: "Explain RAG in one paragraph",
  experimental_telemetry: createLangfuseTelemetry({
    functionId: "chat-assistant",
    userId: "user-123",
    sessionId: "session-456",
    tags: ["production", "chat"],
    metadata: {
      feature: "assistant",
    },
    prompt: {
      name: "assistant/default",
      version: 3,
      isFallback: false,
    },
  }),
});

For global registration, pass the integration once and provide per-call Langfuse context via runtimeContext.langfuse:

import { generateText, registerTelemetry } from "ai";
import { LangfuseVercelAiSdkIntegration } from "@langfuse/vercel-ai-sdk";

registerTelemetry(new LangfuseVercelAiSdkIntegration());

await generateText({
  model,
  prompt: "Summarize this article",
  runtimeContext: {
    langfuse: {
      userId: "user-123",
      sessionId: "session-456",
      tags: ["summaries"],
      metadata: {
        feature: "article-summary",
      },
    },
  },
  experimental_telemetry: {
    functionId: "article-summary",
  },
});

Packages

Package	Description	Environments
@langfuse/client	Langfuse API client for universal JavaScript environments	Universal JS
@langfuse/tracing	Langfuse instrumentation methods based on OpenTelemetry	Node.js 20+
@langfuse/otel	Langfuse OpenTelemetry export helpers	Node.js 20+
@langfuse/openai	Langfuse integration for OpenAI SDK	Universal JS
@langfuse/langchain	Langfuse integration for LangChain	Universal JS
@langfuse/vercel-ai-sdk	Langfuse integration for AI SDK v7	Universal JS