curl --request GET \
  --url https://{tenant}/tyk/apis/{apiID}/versions \
  --header 'X-Tyk-Authorization: <api-key>'

{
  "apis": [
    {
      "expirationDate": "",
      "id": "keyless",
      "internal": false,
      "isDefaultVersion": false,
      "name": "Tyk Test Keyless API",
      "versionName": ""
    },
    {
      "expirationDate": "",
      "id": "1f20d5d2731d47ac9c79fddf826eda00",
      "internal": false,
      "isDefaultVersion": true,
      "name": "Version three Api",
      "versionName": "v2"
    }
  ],
  "status": "success"
}