The Host Object documentation needs to include the tls_accept and tls_connect properties the same way the Proxy Object does.

https://www.zabbix.com/documentation/3.2/manual/api/reference/host/object

https://www.zabbix.com/documentation/3.2/manual/api/reference/proxy/object

Even better would be to include the information in http://www.zabbixbook.com/2016/09/23/how-to-set-host-encryption-parameters-via-the-api/