# Pass the user agent to Hypertune

## Overview

You may need to pass the user agent to Hypertune, e.g. to include it in analytics event payloads, target features or experiments, or provide personalization context to AI loops.

A common pattern is detecting crawlers or bots and returning a specific feature variant early. This can ensure they don't enter an experiment, keeping exposures and analytics clean.

## Setup

To pass the user agent to Hypertune, first add a `userAgent` field to your `User` input type:

```graphql
input User {
  id: String!
  name: String!
  email: String!
  userAgent: String!
}
```

Then get the user agent from the `user-agent` header and pass it to Hypertune:

{% code title="lib/getHypertune.ts" %}

```typescript
import "server-only";
import { unstable_noStore as noStore } from "next/cache";
import { headers } from "next/headers";
import { createSource } from "@/generated/hypertune";

const hypertuneSource = createSource({
  token: process.env.NEXT_PUBLIC_HYPERTUNE_TOKEN!,
});

export default async function getHypertune() {
  noStore();
  await hypertuneSource.initIfNeeded(); // Check for flag updates

  const headersList = await headers();
  const userAgent = headersList.get("user-agent") ?? "";

  return hypertuneSource.root({
    args: {
      context: {
        environment: process.env.NODE_ENV,
        user: { id: "1", name: "Test", email: "hi@test.com", userAgent },
      },
    },
  });
}
```

{% endcode %}

Now you can use the user agent in:

* Analytics event payloads
* Flag targeting rules