Add or modify service set via API

Hi guys!

I can get info about the service set make this request:

curl -k -s -u 'director' -H 'Accept: application/json' -X GET 'https://icinga-host.com/director/serviceset?name=test_set'

My question is, can I import (or modify) any services in the service set via API? Something like this (it’s not working actually):

curl -k -s -u 'director' -H 'Accept: application/json' -X POST 'https://icinga-host.com/director/serviceset?name=test_set' -d '{ "object_name": "test_service", "object_type": "template", "imports": [ "check_queue_tmpl" ], "vars": { "warning": "100", "queue_name": "MY_TEST_QUEUE", "critical": "150" } }'

Thanks!