OpenFeature

OpenFeature is a CNCF incubating open specification for feature flag management. It provides a vendor-agnostic API for evaluating feature flags, enabling developers to use a consistent interface regardless of the underlying feature flag provider. OpenFeature offers SDKs in multiple languages including Go, Java, JavaScript, Python, PHP, and .NET with a provider-based architecture.

OpenFeature publishes 1 API on the APIs.io network: OFREP Core API. Tagged areas include Cloud-Native, Feature Flags, Feature Management, Incubating, and SDK.

OpenFeature’s developer surface includes authentication, documentation, engineering blog, and 5 more developer resources.

🌐 Visit website 📡 Source on GitHub

30.2/100 thin ▬ flat Agent 33/100 agent ready Full breakdown ↓
scored 2026-09-14 · rubric v0.22.0

AccessFreemiumSelf serve⚡ Free to try

1 APIs

Cloud-Native Feature Flags Feature Management Incubating SDK Specification

Kin Score

Kin Score How this is scored →
scored 2026-09-14 · rubric v0.22.0

Composite quality — 30.2/100 · thin

Contract Quality 13.2 / 23

Developer Ergonomics 4.3 / 18

Access Clarity 2.8 / 18

Operational Transparency 1.5 / 12

Contract Governance 0.0 / 11

Discoverability 6.0 / 9

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 33/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 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

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/openfeature: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 1

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

OpenFeature OFREP Core API

**Required**: Core APIs to implement to support OFREP. *This is the minimum set of APIs required for a flag management system to be OFREP compatible.*

Open Collections 2

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

API Collection

OPEN COLLECTION

OpenFeature Remote Evaluation Protocol (OFREP) OFREP Core API

OPEN COLLECTION

Pricing Plans 1

Published pricing tiers and plan structures.

Openfeature Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Openfeature Rate Limits

5 limits

RATE LIMITS

FinOps 1

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

Openfeature Finops

FINOPS

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Openfeature Authentication

apiKey/http · 2 schemes

SECURITY

Openfeature Domain Security

TLSv1.3 · HSTS

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Openfeature Agentic Access

2 operations · 2 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrg

GitHubOrg

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Company 3

The organization behind the API

Website

Website

LinkedIn

Blog

Blog

Source (apis.yml)

aid: openfeature
name: OpenFeature
description: OpenFeature is a CNCF incubating open specification for feature flag management. It provides a vendor-agnostic
  API for evaluating feature flags, enabling developers to use a consistent interface regardless of the underlying feature
  flag provider. OpenFeature offers SDKs in multiple languages including Go, Java, JavaScript, Python, PHP, and .NET with
  a provider-based architecture.
url: https://openfeature.dev
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  label: Freemium · Self-serve signup
  confidence: medium
  source:
  - plans
  - authentication
  - security
  generated: '2026-09-03'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/openfeature.png
tags:
- Cloud-Native
- Feature Flags
- Feature Management
- Incubating
- SDK
- Specification
tags_raw:
- Cloud Native
- Feature Flags
- Feature Management
- Incubating
- SDKs
- Specification
created: '2026-03-16'
modified: '2026-05-19'
specificationVersion: '0.23'
type: Index
apis:
- aid: openfeature:openfeature-ofrep-core-api
  name: OpenFeature OFREP Core API
  description: "**Required**: Core APIs to implement to support OFREP.  \n*This is the minimum set of APIs required for a\
    \ flag management system to be OFREP compatible.*"
  humanURL: https://openfeature.dev/docs/reference/intro
  tags:
  - OFREP Core
  properties:
  - type: OpenAPI
    url: openapi/openfeature-ofrep-core-api-openapi.yml
  - type: Documentation
    url: https://openfeature.dev/docs/reference/intro
common:
- type: Website
  url: https://www.openfeature.dev/
- type: AgenticAccess
  url: agentic-access/openfeature-agentic-access.yml
- type: DomainSecurity
  url: security/openfeature-domain-security.yml
- type: Authentication
  url: authentication/openfeature-authentication.yml
- type: LinkedIn
  url: https://www.linkedin.com/company/openfeature
- type: Documentation
  name: OpenFeature Documentation
  description: Official OpenFeature documentation.
  url: https://openfeature.dev/docs/
- type: GitHubOrg
  name: OpenFeature GitHub
  description: Source code and SDKs.
  url: https://github.com/open-feature
- type: Integrations
  url: https://openfeature.dev/ecosystem/
- type: Blog
  url: https://openfeature.dev/blog/rss.xml
integrations:
- name: OpenFeature
- name: Deploys by Netlify
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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