Use Cases
Common Use Cases
- Temperature-based HVAC control
- Motion-activated lighting
- Door/window security monitoring
- Energy usage optimization
Before You Begin
Prerequisites
- Home Assistant instance with devices
- MQTT broker (Mosquitto)
- IoT sensors publishing to MQTT topics
Walkthrough
Step-by-Step Guide
1
Set Up MQTT Broker
Configure your MQTT broker and verify sensor data is being published.
2
Connect Home Assistant
Set up the Home Assistant MCP Server with your instance URL and access token.
3
Build Automation Logic
Create rules that react to MQTT sensor data and control Home Assistant devices.
async function temperatureAutomation() {
mqtt.subscribe("sensors/living-room/temperature", async (temp) => {
const value = parseFloat(temp);
if (value > 76) {
await homeAssistant.callService({ domain: "climate", service: "set_hvac_mode", entity_id: "climate.living_room", hvac_mode: "cool" });
} else if (value < 68) {
await homeAssistant.callService({ domain: "climate", service: "set_hvac_mode", entity_id: "climate.living_room", hvac_mode: "heat" });
}
});
}4
Add Occupancy Detection
Use motion sensors to automatically adjust devices based on room occupancy.
5
Monitor Energy Usage
Track energy consumption and generate daily efficiency reports.
Examples
Code Examples
typescript
Motion Lighting
mqtt.subscribe("sensors/+/motion", async (payload, topic) => {
const room = topic.split("/")[1];
const motion = JSON.parse(payload).detected;
const action = motion ? "turn_on" : "turn_off";
await homeAssistant.callService({ domain: "light", service: action, entity_id: `light.${room}` });
});Help
Troubleshooting
MQTT messages aren't being received+
Home Assistant is slow to respond+
Quick Info
DifficultyIntermediate
Time Estimate1 hour
Tools
Home Assistant MCP ServerMQTT MCP Server