MQTT

MQTT (Message Queuing Telemetry Transport) is an OASIS-standard, lightweight publish/subscribe messaging transport protocol designed for constrained devices and low-bandwidth, high-latency, or unreliable networks, making it the de-facto messaging protocol for IoT and machine-to-machine (M2M) communication. MQTT is a protocol specification rather than a hosted API: clients connect over TCP/TLS (typically port 1883 or 8883) or WebSocket (8080/8081) to an MQTT broker (such as Mosquitto, HiveMQ, EMQX, or AWS IoT Core) and exchange CONNECT, PUBLISH, SUBSCRIBE, and other control packets defined by the standard. The current standard is MQTT Version 5.0 (OASIS Standard, 7 March 2019); MQTT 3.1.1 remains widely deployed.

MQTT publishes 1 API on the APIs.io network: Version 5.0 Protocol. Tagged areas include MQTT, Messaging, Publish Subscribe, IoT, and M2M.

MQTT’s developer surface includes engineering blog and 6 more developer resources.

🌐 Visit website 📡 Source on GitHub

19.0/100 emerging ▬ flat Agent 22/100 agent aware Full breakdown ↓
scored 2026-07-28 · rubric v0.6

2 APIs

MQTTMessagingPublish SubscribeIoTM2MProtocolOASIS StandardTelemetry

Kin Score

Kin Score How this is scored →
scored 2026-07-28 · rubric v0.6

Composite quality — 19.0/100 · emerging

Contract Quality 12.9 / 25

Developer Ergonomics 0.4 / 20

Commercial Clarity 0.0 / 20

Operational Transparency 0.7 / 13

Governance 0.0 / 12

Discoverability 6.9 / 10

Agent readiness — 22/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 0 / 10

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 6 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/mqtt: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 2

Individual APIs this provider publishes, each with its own machine-readable definition.

Documentation 1

Reference material describing how the API behaves

Specification

Specification

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 2

Properties that don't map to a standard resource type

OASIS Technical Committee

OASIS Technical Committee

Software Listings

Software Listings

Source (apis.yml)

aid: mqtt
name: MQTT
description: 'MQTT (Message Queuing Telemetry Transport) is an OASIS-standard, lightweight publish/subscribe messaging transport
  protocol designed for constrained devices and low-bandwidth, high-latency, or unreliable networks, making it the de-facto
  messaging protocol for IoT and machine-to-machine (M2M) communication. MQTT is a protocol specification rather than a hosted
  API: clients connect over TCP/TLS (typically port 1883 or 8883) or WebSocket (8080/8081) to an MQTT broker (such as Mosquitto,
  HiveMQ, EMQX, or AWS IoT Core) and exchange CONNECT, PUBLISH, SUBSCRIBE, and other control packets defined by the standard.
  The current standard is MQTT Version 5.0 (OASIS Standard, 7 March 2019); MQTT 3.1.1 remains widely deployed.'
type: Index
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/mqtt.png
tags:
- MQTT
- Messaging
- Publish Subscribe
- IoT
- M2M
- Protocol
- OASIS Standard
- Telemetry
url: https://raw.githubusercontent.com/api-evangelist/mqtt/refs/heads/main/apis.yml
created: '2026-05-11'
modified: '2026-05-30'
specificationVersion: '0.19'
apis:
- aid: mqtt:protocol-v5
  name: MQTT Version 5.0 Protocol
  description: OASIS Standard publish/subscribe messaging protocol for IoT and M2M communication. MQTT v5.0 defines the wire
    format and behavior of CONNECT, PUBLISH, SUBSCRIBE, UNSUBSCRIBE, PINGREQ, DISCONNECT and other control packets exchanged
    between MQTT clients and brokers over TCP (typically 1883, or 8883 with TLS) or WebSockets. Authentication is broker-specific
    and may include username/password, X.509 client certificates, or OAuth/JWT enhanced authentication.
  humanURL: https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html
  baseURL: mqtt://broker.example.com:1883
  tags:
  - MQTT 5.0
  - Protocol
  - Publish Subscribe
  - OASIS
  - IoT
  properties:
  - type: Specification
    url: https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html
  - type: Specification PDF
    url: https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.pdf
  - type: OASIS Standard Page
    url: https://www.oasis-open.org/standard/mqtt-v5-0-os/
  - type: Specifications Index
    url: https://mqtt.org/mqtt-specification/
  - type: AsyncAPI
    url: https://raw.githubusercontent.com/api-evangelist/mqtt/refs/heads/main/asyncapi.yml
- aid: mqtt:protocol-v3-1-1
  name: MQTT Version 3.1.1 Protocol
  description: Previous OASIS Standard version of MQTT, still widely deployed across IoT brokers, devices, and cloud platforms.
    MQTT 3.1.1 defines the publish/subscribe messaging semantics, QoS levels 0/1/2, retained messages, and last-will-and-testament
    that are inherited and extended by MQTT 5.0.
  humanURL: https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html
  baseURL: mqtt://broker.example.com:1883
  tags:
  - MQTT 3.1.1
  - Protocol
  - Publish Subscribe
  - OASIS
  - IoT
  properties:
  - type: Specification
    url: https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html
  - type: Specification PDF
    url: https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.pdf
common:
- type: DomainSecurity
  url: security/mqtt-domain-security.yml
- type: GitHubOrganization
  url: https://github.com/mqtt
- type: Website
  url: https://mqtt.org
- type: Specification
  url: https://mqtt.org/mqtt-specification/
- type: OASIS Technical Committee
  url: https://www.oasis-open.org/committees/tc_home.php?wg_abbrev=mqtt
- type: Software Listings
  url: https://mqtt.org/software/
- url: https://www.oasis-open.org/feed/
  type: Blog
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

MQTT

Kin Score

APIs 2

MQTT Version 5.0 Protocol

MQTT Version 3.1.1 Protocol

Security Posture 1

Mqtt Domain Security

Resources