> ## Documentation Index
> Fetch the complete documentation index at: https://docs.agnost.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Vercel AI SDK

> Capture traces from the Vercel AI SDK with experimental_telemetry

The Vercel AI SDK emits `ai.*` spans natively. Wire an OTel exporter pointing at Agnost, then enable telemetry per call with `userId` / `sessionId`.

## 1. Install

**Already have `@opentelemetry/sdk-node` (or another OTel SDK) and `@opentelemetry/exporter-trace-otlp-proto`?** Skip: you only need the existing packages.

**No OTel set up yet?**

```bash theme={null}
npm install @opentelemetry/sdk-node @opentelemetry/exporter-trace-otlp-proto
```

## 2. Wire the OTel exporter pointing at Agnost

**Already exporting OTel?** Append Agnost as an additional span processor on your existing TracerProvider:

```typescript theme={null}
import { BatchSpanProcessor } from '@opentelemetry/sdk-trace-base';
import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-proto';

provider.addSpanProcessor(
  new BatchSpanProcessor(
    new OTLPTraceExporter({
      url: 'https://otel.agnost.ai/v1/traces',
      headers: { 'X-Agnost-Org-ID': process.env.AGNOST_ORG_ID! },
    }),
  ),
);
```

**No OTel yet?** Boot a NodeSDK at startup (e.g. Next.js `instrumentation.ts`):

```typescript theme={null}
import { NodeSDK } from '@opentelemetry/sdk-node';
import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-proto';

new NodeSDK({
  traceExporter: new OTLPTraceExporter({
    url: 'https://otel.agnost.ai/v1/traces',
    headers: { 'X-Agnost-Org-ID': process.env.AGNOST_ORG_ID! },
  }),
}).start();
```

## 3. Pass userId / sessionId per call

```typescript theme={null}
import { generateText } from 'ai';

await generateText({
  model: openai('gpt-4o'),
  prompt: 'Hello',
  experimental_telemetry: {
    isEnabled: true,
    metadata: {
      userId: 'user-42',
      sessionId: 'conv-abc123',
    },
  },
});
```

`experimental_telemetry.isEnabled` defaults to `false`: set it per call.

## References

* [Vercel AI SDK telemetry](https://ai-sdk.dev/docs/ai-sdk-core/telemetry)
* [Add custom metadata](https://ai-sdk.dev/docs/ai-sdk-core/telemetry#telemetry-metadata)