const SiteClient = require('datocms-client').SiteClient;
const client = new SiteClient('YOUR-API-TOKEN');
const subscriptionLimitId = 'locales';
client.subscriptionLimit.find(subscriptionLimitId)
.then((subscriptionLimit) => {
  console.log(subscriptionLimit);
})
.catch((error) => {
  console.error(error);
});

> node example.js
{
  "id": "locales",
  "code": "users",
  "usage": 2,
  "limit": 10
}