json api notifyall

i would like to open a addon on all my clients at once by pressing a maped key on my keyboard
is it posssibe i tried all day but cant get json api to open script from my web browser

http://192.168.1.254:80/jsonrpc?request={"id":1,"jsonrpc":"2.0","method":"Addons.ExecuteAddon","params":{"addonid":"script.doorbell"}


is this correct