Connecting smart lock through zigbee

Now a days there are many smart locks available like kwikset, these locks have ability to connect through zigbee to do more functionality.

I want to develop a project on this, I visited manufacturer's web site but did not find any helpful information, like connecting through MCU, commands etc. need help where should I start from, is it possible that without manufacturer's documentation I can connect to a smart lock and set code on it, perform lock and un-lock actions.

Thanks.