Overview
The MQTT API is defined by one contract file, written in AsyncAPI 3.0.0, the standard format for describing event-driven APIs. Its payloads use the AsyncAPI Schema Object, a superset of JSON Schema Draft 07. The reader itself speaks MQTT 3.1.1. This reference is generated from that contract and is the authority for field names, values, codes and operations: 20 commands and 4 events.
Start with these pages:
- Send Your First Command: exchange
get_versionwith a reader that is already connected, the shortest path to a first reply. - How to Read This Reference: how a command or event page is laid out, and how the names used in the guides map to the contract's keys.
- Versioning and Compatibility: how the contract version changes, and how deprecated fields are marked.
- Changelog: what each contract version changed.
In This Section
Quick Start
From a new reader to live tag reads, in six phases.
How to Read This Reference
How operation pages are organized, and how names map to the wire.
Versioning and Compatibility
How the contract is versioned, and how deprecations are marked.
Changelog
What changed, by firmware release and by contract version.