MQTT

MQTT is the protocol of many home automations and machines: a broker distributes messages by topic, and whoever subscribes to a topic receives them. With the MQTT node, Bellchain sends every alert to a topic on your broker, for example so Home Assistant switches a light or a dashboard shows the last alert. MQTT comes with the Trader plan.

Setting it up

Your broker must be reachable from the internet, encrypted and with a valid certificate (for example from Let’s Encrypt): mqtts:// on port 8883 or WebSocket over TLS with wss://. Cloud brokers such as HiveMQ Cloud or EMQX Cloud come with this; you make your own Mosquitto server reachable via TLS or a reverse proxy with WebSocket.
Create a user of its own for Bellchain that may only write to one topic, such as bellchain/#.
Drag the MQTT node onto the board in the editor, enter Broker, Topic, Username and Password, and click Send test in the properties. Once the test arrives, connect the node to your condition.

What arrives

One message per alert to the topic, by default the same JSON as with the webhook, without a signature (the broker checks username and password):

{
  "id": "3f1c…",
  "type": "alert",
  "version": 1,
  "test": false,
  "time": "2026-10-18T17:00:00.000Z",
  "chain": { "id": "Xy12ab", "name": "BTC Dip Buyer" },
  "action": "q1",
  "message": "BTC Dip Buyer: RSI 14: 28.7 · Price: $77,788",
  "pair": "BTC/USDT",
  "timeframe": "1h",
  "price": 77788,
  "values": [{ "node": "r1", "pin": "out", "label": "RSI 14", "value": 28.7, "text": "28.7" }]
}

Under the node’s advanced settings you choose:

Content: JSON as above or Message only as text, for example for a ticker display.
Delivery: with QoS 1 (default) the broker confirms each message; without a confirmation Bellchain tries again. QoS 0 sends once without confirmation.
Keep last alert: with Keep (retain) the broker stores the last alert; a dashboard gets it right after a restart.

Example: Home Assistant

With the MQTT integration in Home Assistant, an automation reacts to the topic:

automation:
  - alias: "Bellchain: light red on alert"
    trigger:
      - platform: mqtt
        topic: bellchain/alerts
    condition:
      - condition: template
        value_template: "{{ not trigger.payload_json.test }}"
    action:
      - service: light.turn_on
        target:
          entity_id: light.office
        data:
          color_name: red

When something does not arrive

Reason in the history	Meaning
`mqtt_auth`, `mqtt_not_authorized`	Username or password wrong, or the user may not connect. Bellchain does not try again and lets you know.
`mqtt_tls`	The broker’s certificate is invalid, expired or self-signed.
`mqtt_url_not_tls`	The address starts with `mqtt://` or `ws://`; Bellchain sends encrypted only.
`mqtt_private_address`	The broker is on your own network, such as `192.168.…` or `homeassistant.local`.
`mqtt_network`, `mqtt_timeout`, `mqtt_unavailable`, `mqtt_closed`	The broker was not reachable or did not answer; Bellchain tries again later.
`mqtt_ws_not_found`	There is no WebSocket under the path of the `wss://` address; often `/mqtt` is missing at the end.

Bellchain speaks MQTT 3.1.1 and connects anew for every alert: connect, publish, disconnect, with a client ID bellchain-… and no stored session.

Version 2026.10.25.16 · Changelog