diff --git a/source/_components/light.mqtt_json.markdown b/source/_components/light.mqtt_json.markdown
index 6e70c8be891..cd4f65737e5 100644
--- a/source/_components/light.mqtt_json.markdown
+++ b/source/_components/light.mqtt_json.markdown
@@ -56,6 +56,10 @@ name:
   required: false
   type: string
   default: MQTT JSON Light
+unique_id:
+   description: An ID that uniquely identifies this light. If two lights have the same unique ID, Home Assistant will raise an exception.
+   required: false
+   type: string
 command_topic:
   description: The MQTT topic to publish commands to change the light’s state.
   required: true
@@ -262,4 +266,4 @@ Home Assistant expects the hue values to be in the range 0 to 360 and the satura
 
 - [esphomelib](https://github.com/OttoWinter/esphomelib) is a library for ESP8266 and ESP32 boards that has many of Home Assistant's MQTT features (like [discovery](/docs/mqtt/discovery/)) pre-implemented and provides high-level abstractions for components such as lights or sensors.
 
-- [AiLight](https://github.com/stelgenhof/AiLight) is a custom firmware for the Ai-Thinker (and equivalent) RGBW WiFi light bulbs that has an ESP8266 onboard and controlled by the MY9291 LED driver. It implements the [MQTT JSON light](/components/light.mqtt_json/) platform and supports ON/OFF, RGBW colours, brightness, colour temperature, flashing and transitions. Also it includes [MQTT Auto Discovery](/docs/mqtt/discovery/)) and the MQTT Last Will and Testament is enabled as well.
\ No newline at end of file
+- [AiLight](https://github.com/stelgenhof/AiLight) is a custom firmware for the Ai-Thinker (and equivalent) RGBW WiFi light bulbs that has an ESP8266 onboard and controlled by the MY9291 LED driver. It implements the [MQTT JSON light](/components/light.mqtt_json/) platform and supports ON/OFF, RGBW colours, brightness, colour temperature, flashing and transitions. Also it includes [MQTT Auto Discovery](/docs/mqtt/discovery/)) and the MQTT Last Will and Testament is enabled as well.