# identify

Learn how to identify the current visitor on the server.

This function identifies the current visitor by re-issuing the user token for the given customer.

Call it from a server action with the action's load context, typically after your own authentication succeeds. The updated token is persisted when the [response cookies are written](/reference/sdk/hydrogen/api/setup/write-croct-cookies).

## Signature

This function has the following signature:

```ts
function identify(userId: string, scope: CroctContext): Promise<void>;
```

## Example

Identify a customer in a login action, after your own authentication succeeds:

**app/routes/login.tsx**

```tsx
import {redirect} from 'react-router';
import {identify} from '@croct/plug-hydrogen/server';
import type {Route} from './+types/login';

export async function action({request, context}: Route.ActionArgs) {
  const form = await request.formData();

  await identify(String(form.get('customerId')), context);

  return redirect('/account');
}
```

## Parameters

The following list describes the supported parameters:

- `userId`: `string`

  The ID of the customer to identify.

- `scope`: `CroctContext`

  The Hydrogen load context for the current request.