> ## Documentation Index
> Fetch the complete documentation index at: https://arizeai-433a7140.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Anthropic SDK TypeScript

> Instrument and observe Anthropic calls in TypeScript/Node.js

This module provides automatic instrumentation for the [Anthropic SDK TypeScript](https://github.com/anthropics/anthropic-sdk-typescript), which may be used in conjunction with [@arizeai/phoenix-otel](https://www.npmjs.com/package/@arizeai/phoenix-otel).

## Install

```bash theme={null}
npm install @arizeai/openinference-instrumentation-anthropic @anthropic-ai/sdk @arizeai/phoenix-otel
```

## Setup

To instrument your application, use the `register` function from `@arizeai/phoenix-otel` and manually instrument the Anthropic SDK.

Create the `instrumentation.ts` file:

```typescript expandable theme={null}
import { register } from "@arizeai/phoenix-otel";
import Anthropic from "@anthropic-ai/sdk";
import { AnthropicInstrumentation } from "@arizeai/openinference-instrumentation-anthropic";

// Initialize Phoenix tracing
const tracerProvider = register({
  projectName: "anthropic-app",
  // If Phoenix is running elsewhere:
  // url: "https://your-phoenix.example.com",
  // apiKey: process.env.PHOENIX_API_KEY,
  // If using self-hosted Phoenix:
  // url: "http://localhost:6006",
});

// Set up Anthropic instrumentation
const instrumentation = new AnthropicInstrumentation();
instrumentation.manuallyInstrument(Anthropic);

console.log("Anthropic instrumentation registered");
```

## Run Anthropic

Import the `instrumentation.ts` file first, then use Anthropic as usual.

```typescript expandable theme={null}
import "./instrumentation.js";
import Anthropic from "@anthropic-ai/sdk";

// set ANTHROPIC_API_KEY in environment, or pass it in arguments
const anthropic = new Anthropic({
  apiKey: process.env.ANTHROPIC_API_KEY,
});

async function main() {
  const message = await anthropic.messages.create({
    model: "claude-sonnet-4-20250514",
    max_tokens: 1024,
    messages: [{ role: "user", content: "Write a haiku about recursion." }],
  });

  console.log(message.content);
}

main();
```

## Observe

After setting up instrumentation and running your Anthropic application, traces will appear in the Phoenix UI for visualization and analysis.

## Custom Tracer Provider

You can specify a custom tracer provider for Anthropic instrumentation:

### Pass tracerProvider on instantiation

```typescript expandable theme={null}
import { register } from "@arizeai/phoenix-otel";
import Anthropic from "@anthropic-ai/sdk";
import { AnthropicInstrumentation } from "@arizeai/openinference-instrumentation-anthropic";

const tracerProvider = register({
  projectName: "anthropic-app",
});

const instrumentation = new AnthropicInstrumentation({
  tracerProvider,
});
instrumentation.manuallyInstrument(Anthropic);
```

### Set tracerProvider after instantiation

```typescript theme={null}
const instrumentation = new AnthropicInstrumentation();
instrumentation.setTracerProvider(tracerProvider);
instrumentation.manuallyInstrument(Anthropic);
```

## Resources

* [NPM Package](https://www.npmjs.com/package/@arizeai/openinference-instrumentation-anthropic)

* [OpenInference package for Anthropic SDK TypeScript](https://github.com/Arize-ai/openinference/tree/main/js/packages/openinference-instrumentation-anthropic)