You can render a selected list of attributes via the fields[resource_type]=attribute_name query parameter.

Here is an example request to render a list of servers with only the hostname and label of each record.

curl --request GET \
     --url 'https://api.maxihost.com/servers?fields[servers]=hostname,label' \
     --header 'Accept: application/vnd.maxihost.v2+json'