CloudEvents

CloudEvents is a CNCF graduated specification for describing event data in a common way. It provides a consistent format for event metadata across services, platforms, and systems, enabling interoperability between event producers and consumers. The specification includes protocol bindings for HTTP, AMQP, Kafka, MQTT, and NATS, along with SDKs in multiple languages.

CloudEvents publishes 2 APIs on the APIs.io network: Specification and Subscriptions API. Tagged areas include Cloud Native, Events, Graduated, Interoperability, and Messaging.

The CloudEvents catalog on APIs.io includes 1 event-driven AsyncAPI specification, 1 JSON-LD context, and 3 Spectral governance rulesets.

CloudEvents’ developer surface includes documentation, getting-started guide, engineering blog, changelog, and 10 more developer resources.

🌐 Visit website 📡 Source on GitHub

42.4/100 developing ▼ -8.3 Agent 27/100 agent aware Full breakdown ↓
scored 2026-07-28 · rubric v0.6

AccessFree

12 APIs

Cloud NativeEventsGraduatedInteroperabilityMessagingSpecification

Kin Score

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

Composite quality — 42.4/100 · developing

Contract Quality 18.1 / 25

Developer Ergonomics 5.7 / 20

Commercial Clarity 5.8 / 20

Operational Transparency 5.5 / 13

Governance 5.0 / 12

Discoverability 7.2 / 10

Agent readiness — 27/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 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 7 / 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/cloudevents: 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 12

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

Rate Limits 1

Documented rate limits and quota policies.

Cloudevents Rate Limits

1 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

JSON Schema 6

Standalone JSON Schema definitions for this provider's data models.

Get Started 1

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

Documentation 4

Reference material describing how the API behaves

Documentation

JSONSchema

OpenAPI

AsyncAPI

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Design & Contract 2

Pagination, idempotency, versioning, errors, and events

JSONLD

JSONLD

Spectral

Spectral

Build 2

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

SDKs

SDKs

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Operate 1

Status, limits, changes, and where to get help

ChangeLog

ChangeLog

Company 2

The organization behind the API

Website

Website

Blog

Blog

Source (apis.yml)

aid: cloudevents
name: CloudEvents
description: CloudEvents is a CNCF graduated specification for describing event data in a common way. It provides a consistent
  format for event metadata across services, platforms, and systems, enabling interoperability between event producers and
  consumers. The specification includes protocol bindings for HTTP, AMQP, Kafka, MQTT, and NATS, along with SDKs in multiple
  languages.
url: https://cloudevents.io
accessModel:
  pricing: free
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Free
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/cloudevents.png
tags:
- Cloud Native
- Events
- Graduated
- Interoperability
- Messaging
- Specification
created: '2026-03-16'
modified: '2026-05-19'
kind: standard
x-governance: CNCF (Cloud Native Computing Foundation)
x-status: Graduated
x-spec-version: 1.0.2
specificationVersion: '0.19'
type: Index
apis:
- aid: cloudevents:cloudevents-spec
  name: CloudEvents Specification
  description: The CloudEvents specification defines a set of metadata attributes that must be present in every event, including
    source, type, id, and specversion. It provides a vendor-neutral way to describe events that enables consistent routing,
    filtering, and processing across different systems and cloud providers.
  humanURL: https://cloudevents.io/
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/spec.md
  - type: Reference
    url: https://github.com/cloudevents/spec/blob/main/cloudevents/spec.md
  - type: GitHubRepository
    url: https://github.com/cloudevents/spec
  - type: ChangeLog
    url: https://github.com/cloudevents/spec/releases
  - type: JSONSchema
    url: json-schema/cloudevents-event-schema.json
  - type: AsyncAPI
    url: asyncapi/cloudevents-http-asyncapi.yml
  tags:
  - Events
  - Specification
  - Standards
- aid: cloudevents:cloudevents-http-binding
  name: CloudEvents HTTP Protocol Binding
  description: The HTTP protocol binding defines how CloudEvents are transported using HTTP, including structured content
    mode where the entire event is in the HTTP body, and binary content mode where event attributes are mapped to HTTP headers.
    This enables REST APIs to produce and consume standardized events.
  humanURL: https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/bindings/http-protocol-binding.md
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/bindings/http-protocol-binding.md
  - type: Reference
    url: https://github.com/cloudevents/spec/blob/main/cloudevents/bindings/http-protocol-binding.md
  tags:
  - HTTP
  - Protocol Binding
  - REST
- aid: cloudevents:cloudevents-kafka-binding
  name: CloudEvents Kafka Protocol Binding
  description: The Kafka protocol binding for CloudEvents defines how events are mapped to Apache Kafka messages. It specifies
    how CloudEvents attributes are encoded as Kafka message headers and how the event payload is placed in the Kafka message
    value, enabling standardized event interchange over Kafka topics.
  humanURL: https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/bindings/kafka-protocol-binding.md
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/bindings/kafka-protocol-binding.md
  - type: Reference
    url: https://github.com/cloudevents/spec/blob/main/cloudevents/bindings/kafka-protocol-binding.md
  tags:
  - Kafka
  - Messaging
  - Protocol Binding
- aid: cloudevents:cloudevents-amqp-binding
  name: CloudEvents AMQP Protocol Binding
  description: The AMQP protocol binding for CloudEvents defines how events are mapped to OASIS AMQP 1.0 messages. In structured
    content mode, event attributes and data are placed in the AMQP message application data section; in binary content mode,
    event data is placed as-is with attributes mapped to AMQP message properties.
  humanURL: https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/bindings/amqp-protocol-binding.md
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/spec/blob/v1.0.2/cloudevents/bindings/amqp-protocol-binding.md
  - type: Reference
    url: https://github.com/cloudevents/spec/blob/main/cloudevents/bindings/amqp-protocol-binding.md
  tags:
  - AMQP
  - Messaging
  - Protocol Binding
- aid: cloudevents:cloudevents-mqtt-binding
  name: CloudEvents MQTT Protocol Binding
  description: The MQTT protocol binding for CloudEvents defines how events are mapped to MQTT 3.1.1 and MQTT 5.0 messages.
    It supports both structured and binary content modes for IoT and constrained device environments that use MQTT as their
    messaging protocol.
  humanURL: https://github.com/cloudevents/spec/blob/main/cloudevents/bindings/mqtt-protocol-binding.md
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/spec/blob/main/cloudevents/bindings/mqtt-protocol-binding.md
  tags:
  - IoT
  - MQTT
  - Protocol Binding
- aid: cloudevents:cloudevents-nats-binding
  name: CloudEvents NATS Protocol Binding
  description: The NATS protocol binding for CloudEvents defines how events are mapped to NATS messages. It enables CloudEvents
    to be produced and consumed over the NATS messaging system, supporting both publish/subscribe and request/reply patterns.
  humanURL: https://github.com/cloudevents/spec/blob/main/cloudevents/bindings/nats-protocol-binding.md
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/spec/blob/main/cloudevents/bindings/nats-protocol-binding.md
  tags:
  - Messaging
  - NATS
  - Protocol Binding
- aid: cloudevents:cloudevents-cesql
  name: CloudEvents SQL (CESQL)
  description: CloudEvents SQL (CESQL) is a v1.0 specification that defines a standardized query language for filtering and
    routing CloudEvents based on their attributes. It provides a SQL-like syntax for writing event filter expressions that
    can be used across different event processing platforms and systems.
  humanURL: https://github.com/cloudevents/spec/blob/main/cesql/spec.md
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/spec/blob/main/cesql/spec.md
  tags:
  - Filtering
  - Specification
  - SQL
- aid: cloudevents:cloudevents-sdk-go
  name: CloudEvents Go SDK
  description: The official Go SDK for CloudEvents provides libraries for producing and consuming CloudEvents in Go applications.
    It supports all CloudEvents protocol bindings and content modes, and includes client implementations for HTTP, Kafka,
    and other transports.
  humanURL: https://github.com/cloudevents/sdk-go
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://cloudevents.github.io/sdk-go/
  - type: GitHubRepository
    url: https://github.com/cloudevents/sdk-go
  tags:
  - Client Library
  - Go
  - SDK
- aid: cloudevents:cloudevents-sdk-javascript
  name: CloudEvents JavaScript SDK
  description: The official JavaScript SDK for CloudEvents provides libraries for producing and consuming CloudEvents in Node.js
    and browser environments. It supports structured and binary content modes over HTTP and other transports.
  humanURL: https://github.com/cloudevents/sdk-javascript
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/sdk-javascript/blob/main/README.md
  - type: GitHubRepository
    url: https://github.com/cloudevents/sdk-javascript
  tags:
  - Client Library
  - JavaScript
  - SDK
- aid: cloudevents:cloudevents-sdk-java
  name: CloudEvents Java SDK
  description: The official Java SDK for CloudEvents provides libraries for producing and consuming CloudEvents in Java applications.
    It includes support for HTTP, Kafka, and other transports, and integrates with popular Java frameworks.
  humanURL: https://github.com/cloudevents/sdk-java
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/sdk-java/blob/main/README.md
  - type: GitHubRepository
    url: https://github.com/cloudevents/sdk-java
  tags:
  - Client Library
  - Java
  - SDK
- aid: cloudevents:cloudevents-sdk-python
  name: CloudEvents Python SDK
  description: The official Python SDK for CloudEvents provides libraries for producing and consuming CloudEvents in Python
    applications. It supports HTTP transport bindings and both structured and binary content modes.
  humanURL: https://github.com/cloudevents/sdk-python
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  properties:
  - type: Documentation
    url: https://github.com/cloudevents/sdk-python/blob/main/README.md
  - type: GitHubRepository
    url: https://github.com/cloudevents/sdk-python
  tags:
  - Client Library
  - Python
  - SDK
- aid: cloudevents:cloudevents-subscriptions-api
  name: CloudEvents Subscriptions API
  description: Operations for creating and managing event delivery subscriptions. Each subscription specifies a source of
    events, optional filter criteria, and a sink where matched events are delivered.
  humanURL: https://cloudevents.io/
  tags:
  - Subscriptions
  properties:
  - type: OpenAPI
    url: openapi/cloudevents-subscriptions-api-openapi.yml
  - type: Documentation
    url: https://github.com/cloudevents/spec/blob/main/subscriptions/spec.md
common:
- type: AgenticAccess
  url: agentic-access/cloudevents-agentic-access.yml
- type: DomainSecurity
  url: security/cloudevents-domain-security.yml
- type: Website
  url: https://cloudevents.io
- type: Documentation
  url: https://github.com/cloudevents/spec
- type: GettingStarted
  url: https://github.com/cloudevents/spec/blob/main/cloudevents/primer.md
- type: Blog
  url: https://cloudevents.io/blog/
- type: GitHubOrganization
  url: https://github.com/cloudevents
- type: SDKs
  url: https://github.com/cloudevents/spec/blob/main/cloudevents/SDK.md
- type: ChangeLog
  url: https://github.com/cloudevents/spec/releases
- type: JSONSchema
  url: json-schema/cloudevents-event-schema.json
- type: OpenAPI
  url: openapi/cloudevents-subscriptions-openapi.yml
- type: AsyncAPI
  url: asyncapi/cloudevents-http-asyncapi.yml
- type: JSONLD
  url: json-ld/cloudevents-context.jsonld
- type: Spectral
  url: rules/cloudevents-rules.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

CloudEvents

APIs 12

Open Collections 1

Pricing Plans 1

Rate Limits 1

FinOps 1

Event Specifications 1

Semantic Vocabularies 1

Spectral Rules 3