When Mycroft sends a request to HA ( ie: turn on some entity ), HA sends back nothing but an empty json {}. This is the same whether the request was sucessful or not. There is no indication of success, entity already at desired state, entity not available or entity does not exist.
Do you know what HA should be responding with? I assume this is not expected behaviour.
Where are you testing the response from HA?
I haven’t studied the HA API so I have no idea what the proper response may be. For all I know the empty jason {} may very well be specified. I my my opinion that is inadequate. I think that HA should provide Mycroft with some sort of error message so the user can be alerted.
I was using Wireshark to intercept the messaging. The apps communicate with http messaging. This is probably what some refer to as a Restful API. When Mycroft wants to initiate an action it first sends a status request to HA. This is not specific to any entity on HA and it responds with what appears to be its entire entity status data base. Even with my minimal installation the message is huge. Mycroft then sends a short on/off message. Mycroft may send the wrong entity. That is addressed in my other post about Mycroft misinterpreting the entity name.