import Courier from '@trycourier/courier';

const client = new Courier({
  apiKey: process.env['COURIER_API_KEY'], // This is the default and can be omitted
});

const response = await client.users.preferences.retrieveTopic('topic_id', { user_id: 'user_id' });

console.log(response.topic);

{
  "topic": {
    "custom_routing": [
      "direct_message"
    ],
    "default_status": "OPTED_IN",
    "has_custom_routing": true,
    "status": "OPTED_IN",
    "topic_id": "PT91W47CKEMP6PW0RYVN3F08F2YE",
    "topic_name": "string"
  }
}