diff --git a/homeassistant/observers.py b/homeassistant/observers.py
index 17000ed7bc0..8981c1b5975 100644
--- a/homeassistant/observers.py
+++ b/homeassistant/observers.py
@@ -29,8 +29,8 @@ STATE_CATEGORY_SUN = "weather.sun"
 STATE_ATTRIBUTE_NEXT_SUN_RISING = "next_rising"
 STATE_ATTRIBUTE_NEXT_SUN_SETTING = "next_setting"
 
-STATE_CATEGORY_ALL_DEVICES = 'all_devices'
-STATE_CATEGORY_DEVICE_FORMAT = '{}'
+STATE_CATEGORY_ALL_DEVICES = 'device.ALL'
+STATE_CATEGORY_DEVICE_FORMAT = 'device.{}'
 
 STATE_CATEGORY_CHROMECAST = 'chromecast'