The API is accessible through your regular account.
The documentation is available here
1) Login and get the session JWT.
Get a new token using the login endpoint or verify the validity of an existing token. If the token expired, you can refresh it.
The JWT authentication token must be provided for all requests in the Authorization = Bearer <token> HTTP header.
2) Perform a query and list the zones matching the query
Either get all zones (for a set of sources) within a given bounding box using the zone endpoint. Alternatively, you can perform custom queries using the query endpoint. The query language is documented here.
3) Retrieve the zones
As the zone listing query returns a list of Zones IDs you need to retrieve the zone’s geometry and associated labels by calling the Zone endpoint for each Zone id.