const SiteClient = require('datocms-client').SiteClient;
const client = new SiteClient('YOUR-API-TOKEN');
client.accessToken.create({
  name: 'Read-only API token',
  canAccessCda: true,
  canAccessCdaPreview: true,
  canAccessCma: true,
  role: '34'
})
.then((accessToken) => {
  console.log(accessToken);
})
.catch((error) => {
  console.error(error);
});

> node example.js
{
  "id": "312",
  "name": "Read-only API token",
  "token": "XXXXXXXXXXXXXXX",
  "canAccessCda": true,
  "canAccessCdaPreview": true,
  "canAccessCma": true,
  "hardcodedType": "",
  "role": "34"
}