Introduction to LoT

What is LoT?

LoT (Language of Things) is a human-readable language for IoT automation. It uses near-English syntax to define logic, data structures, and integrations—all executed directly within the Coreflux MQTT broker. LoT is built by defining Actions, Models, Connectors, and Rules. Each one handles a different part of your automation, and inside them you use commands like PUBLISH, SET, and GET to make things happen. An agent (DEFINE AGENT) is a further entity: a tool-using assistant that runs on a TYPE LLM connector. See AI Connectors and Agents.

Think of LoT as SQL for real-time MQTT data. Just as SQL transforms database records, LoT transforms live MQTT streams.

Like building with LEGO blocks. You pick the right block for the job — Actions for logic, Models for data structure, Connectors for connections, Rules for security — and snap them together into a complete system.

The Building Blocks

Each construct is created with the DEFINE keyword:

Construct	Purpose	Trigger Types
Actions	Execute logic when events occur	Time, Topic, System events, Manual
Models	Structure MQTT data into JSON schemas	Topic values, Action calls
Connectors	Connect to external systems	Topic patterns
Rules	Control who can publish/subscribe	Client identity, Topic patterns
Agents	A tool-using assistant on a `TYPE LLM` connector	MQTT, another agent, or `CALL AGENT`

Actions

Event-driven logic triggered by time or MQTT topics.

Models

Data schemas that structure MQTT messages into JSON.

Rules

Access control for topics and operations.

Connectors

Connect to databases, brokers, and external services.

Agents

A tool-using assistant on a TYPE LLM connector.

How They Work Together

A typical LoT solution combines all four building blocks. Each definition below uses valid LoT syntax — the same patterns you will see in the Models, Actions, Connectors, and Rules references.

-- 1. MODEL: When raw temperature updates, publish structured JSON per sensor
DEFINE MODEL SensorReading WITH TOPIC "sensors/+/formatted"
    ADD STRING "sensor_id" WITH TOPIC "sensors/+/id"
    ADD DOUBLE "temperature" WITH TOPIC "sensors/+/raw" AS TRIGGER
    ADD STRING "unit" WITH "celsius"
    ADD STRING "timestamp" WITH TIMESTAMP "UTC"

-- 2. ACTION: React to formatted readings and raise alerts
DEFINE ACTION TemperatureAlert
ON TOPIC "sensors/+/formatted" DO
    SET "sensor_id" WITH TOPIC POSITION 2
    SET "temp" WITH (GET JSON "temperature" IN PAYLOAD AS DOUBLE)
    IF {temp} > 80 THEN
        PUBLISH TOPIC "alerts/" + {sensor_id} + "/high_temp" WITH "Temperature above threshold"

-- 3. CONNECTOR: Persist sensor traffic to PostgreSQL
DEFINE CONNECTOR SensorDB WITH TYPE POSTGRESQL
    ADD SQL_CONFIG
        WITH SERVER "postgres.example.com"
        WITH PORT '5432'
        WITH DATABASE "iot_data"
        WITH USERNAME "iot_user"
        WITH PASSWORD "secure_password"
    ADD EVENT StoreSensorData
        WITH SOURCE_TOPIC "sensors/#"
        WITH QUERY "INSERT INTO sensor_readings (topic, payload) VALUES ('{topic}', '{value.json}')"

-- 4. RULE: Only supervisors (or root) may publish to alert topics
DEFINE RULE RestrictAlertPublish WITH PRIORITY 100 FOR Publish TO TOPIC "alerts/#"
    IF USER IN GROUP "supervisors" OR USER IS "root" THEN
        ALLOW
    ELSE
        DENY

Step	What Happens
1	When `sensors/temp001/raw` updates, the Model publishes JSON to `sensors/temp001/formatted`
2	The Action reads `temperature` from that JSON and publishes to `alerts/temp001/high_temp` when it exceeds 80
3	The Connector inserts every message under `sensors/#` (raw, formatted, and related topics) into PostgreSQL
4	The Rule denies publish to `alerts/#` unless the client is in `supervisors` or is `root`

What You’ll Learn on This Page

Below you’ll find practical examples showing LoT in action - from simple heartbeats to data transformation. Each example demonstrates a core capability you can implement immediately.

Hello World

Three examples showing what LoT can do:

DEFINE ACTION Heartbeat
ON EVERY 5 SECONDS DO
    PUBLISH TOPIC "system/alive" WITH "ok"

DEFINE ACTION Echo
ON TOPIC "input/message" DO
    PUBLISH TOPIC "output/message" WITH PAYLOAD

DEFINE MODEL SensorData WITH TOPIC "sensors/formatted"
    ADD STRING "id" WITH "TEMP001"
    ADD DOUBLE "value" WITH TOPIC "sensors/raw" AS TRIGGER

Example	Trigger	What it does
Heartbeat	Every 5 seconds	Publishes “ok” to indicate the system is alive
Echo	Message on `input/message`	Forwards the payload to another topic
SensorData	Value on `sensors/raw`	Formats raw sensor data into structured JSON

Quick Start

Coreflux MQTT Broker

LoT Language

Coreflux HUB

VS Code - LoT Notebooks

Coreflux Portal

Using AI with Coreflux

Product Updates

What is LoT?

The Building Blocks

Actions

Models

Rules

Connectors

Agents

How They Work Together

What You’ll Learn on This Page

Hello World

Next Steps

Best Practices & Patterns

Actions Overview

​What is LoT?

​The Building Blocks

Actions

Models

Rules

Connectors

Agents

​How They Work Together

​What You’ll Learn on This Page

​Hello World

​Next Steps

Best Practices & Patterns

Actions Overview

What is LoT?

The Building Blocks

How They Work Together

What You’ll Learn on This Page

Hello World

Next Steps