Home-automation standard for custom devices
So is there a standard for house automation related to a particular protocol or not, where devices can be controlled by a compliant software and where devices can communicate their capabilities ?


No. There are many "standards".



The OpenHAB open-source project (as in open-habitat) has done a huge amount of work on this with protocols hacked for many commercially available systems. They have an OpenHAB application to run on Linux (Raspberry Pi is suitable platform) and Android (at least) app to control the system. Using their platform you can integrate devices from all the vendors they support.