SSO website screenshot

SSO

Single Sign-On (SSO) is an authentication technology that allows users to log in once and gain access to multiple related applications and services without re-authenticating. SSO implementations rely on protocols such as SAML 2.0, OpenID Connect (OIDC), and OAuth 2.0. Major identity providers including Okta, Microsoft Entra ID, Google, Ping Identity, Auth0, and Keycloak expose SSO APIs that allow applications to integrate federated authentication, token exchange, assertion validation, and session management.

SSO publishes 8 APIs on the APIs.io network, including Authentication API, Authorization API, Discovery API, and 5 more. Tagged areas include Authentication, Authorization, Identity, OAuth, and OIDC.

The SSO catalog on APIs.io includes 1 JSON-LD context and 2 Spectral governance rulesets.

SSO’s developer surface includes authentication, engineering blog, and 11 more developer resources.

🌐 Visit website 📡 Source on GitHub
46.3/100 developing ▬ flat Agent 41/100 agent ready Full breakdown ↓
scored 2026-08-05 · rubric v0.9.1
AccessFreemiumSelf serve⚡ Free to try
8 APIs
AuthenticationAuthorizationIdentityOAuthOIDCSAMLSecuritySingle Sign-OnSSO

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-05 · rubric v0.9.1
Composite quality — 46.3/100 · developing
Contract Quality 16.0 / 25
Developer Ergonomics 2.6 / 20
Commercial Clarity 7.9 / 20
Operational Transparency 4.8 / 13
Governance 8.3 / 12
Discoverability 6.9 / 10
Agent readiness — 41/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
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
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/sso: 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 8

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

SSO Authentication API

SAML 2.0 authentication request and response endpoints for initiating and completing SSO login flows.

SSO Authorization API

OIDC authorization endpoints for initiating authentication flows and exchanging authorization codes for tokens.

SSO Discovery API

OpenID Provider Discovery endpoint for retrieving provider configuration metadata.

SSO Keys API

JSON Web Key Set (JWKS) endpoint for retrieving public keys used to verify ID token signatures.

SSO Logout API

SAML 2.0 Single Logout (SLO) endpoints for terminating SSO sessions across all service providers.

SSO Metadata API

SAML 2.0 metadata endpoints for exchanging federation configuration between identity providers and service providers.

SSO Token API

Token endpoint operations for exchanging authorization codes and refresh tokens for access tokens and ID tokens.

SSO User Info API

UserInfo endpoint for retrieving authenticated user profile claims.

Scroll for all 8

Open Collections 2

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

OpenID Connect (OIDC) SSO API

OPEN COLLECTION

SAML 2.0 SSO API

OPEN COLLECTION

Pricing Plans 1

Published pricing tiers and plan structures.

Sso Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Sso Rate Limits

5 limits

RATE LIMITS

FinOps 1

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

Sso Finops

FINOPS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Sso Context

32 classes · 5 properties

JSON-LD

Spectral Rules 2

Spectral governance rulesets for linting and validating these APIs.

SSO API Rules

5 rules · 3 warnings 2 info

SPECTRAL

SSO API Rules

10 rules · 3 errors 7 warnings

SPECTRAL

JSON Schema 2

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

OIDC Token Response

6 properties

JSON SCHEMA

SAML Assertion

8 properties

JSON SCHEMA

JSON Structure 1

JSON Structure definitions describing this provider's data shapes.

Sso Saml Assertion Structure

8 properties

JSON STRUCTURE

Examples 1

Example request and response payloads for these APIs.

Sso Oidc Token Response Example

6 fields

EXAMPLE

Security Posture 2

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

Sso Authentication

http · 1 scheme

SECURITY

Sso Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

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

Sso Agentic Access

11 operations · 4 acting · 1 human-in-the-loop

11 operations · 4 acting

AGENTIC

Resources

Documentation 5

Reference material describing how the API behaves

Specification
Specification
 Specification
Specification
 Specification
Specification
 JSONSchema
JSONSchema
 JSONSchema
JSONSchema

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess
AgenticAccess

Design & Contract 3

Pagination, idempotency, versioning, errors, and events

JSONLD
JSONLD
 Vocabulary
Vocabulary
 SpectralRules
SpectralRules

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 1

The organization behind the API

Blog
Blog

Source (apis.yml)

apis.yml Raw ↑ 
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  label: Freemium · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/sso.png
name: SSO
description: Single Sign-On (SSO) is an authentication technology that allows users to log in once and gain access to multiple
  related applications and services without re-authenticating. SSO implementations rely on protocols such as SAML 2.0, OpenID
  Connect (OIDC), and OAuth 2.0. Major identity providers including Okta, Microsoft Entra ID, Google, Ping Identity, Auth0,
  and Keycloak expose SSO APIs that allow applications to integrate federated authentication, token exchange, assertion validation,
  and session management.
url: https://github.com/api-evangelist/sso
tags:
- Authentication
- Authorization
- Identity
- OAuth
- OIDC
- SAML
- Security
- Single Sign-On
- SSO
created: '2025-01-01'
modified: '2026-05-19'
apis:
- aid: sso:sso-authentication-api
  name: SSO Authentication API
  description: SAML 2.0 authentication request and response endpoints for initiating and completing SSO login flows.
  humanURL: https://www.oasis-open.org/standards#samlv2.0
  baseURL: https://your-idp.example.com
  tags:
  - Authentication
  properties:
  - type: OpenAPI
    url: openapi/sso-authentication-api-openapi.yml
  - type: Documentation
    url: https://www.oasis-open.org/standards#samlv2.0
  - type: Documentation
    url: https://wiki.oasis-open.org/security/FrontPage
  - type: Documentation
    url: https://openid.net/connect/
  - type: Specification
    url: https://openid.net/developers/specs/
- aid: sso:sso-authorization-api
  name: SSO Authorization API
  description: OIDC authorization endpoints for initiating authentication flows and exchanging authorization codes for tokens.
  humanURL: https://www.oasis-open.org/standards#samlv2.0
  baseURL: https://your-idp.example.com
  tags:
  - Authorization
  properties:
  - type: OpenAPI
    url: openapi/sso-authorization-api-openapi.yml
  - type: Documentation
    url: https://www.oasis-open.org/standards#samlv2.0
  - type: Documentation
    url: https://wiki.oasis-open.org/security/FrontPage
  - type: Documentation
    url: https://openid.net/connect/
  - type: Specification
    url: https://openid.net/developers/specs/
- aid: sso:sso-discovery-api
  name: SSO Discovery API
  description: OpenID Provider Discovery endpoint for retrieving provider configuration metadata.
  humanURL: https://www.oasis-open.org/standards#samlv2.0
  baseURL: https://your-idp.example.com
  tags:
  - Discovery
  properties:
  - type: OpenAPI
    url: openapi/sso-discovery-api-openapi.yml
  - type: Documentation
    url: https://www.oasis-open.org/standards#samlv2.0
  - type: Documentation
    url: https://wiki.oasis-open.org/security/FrontPage
  - type: Documentation
    url: https://openid.net/connect/
  - type: Specification
    url: https://openid.net/developers/specs/
- aid: sso:sso-keys-api
  name: SSO Keys API
  description: JSON Web Key Set (JWKS) endpoint for retrieving public keys used to verify ID token signatures.
  humanURL: https://www.oasis-open.org/standards#samlv2.0
  baseURL: https://your-idp.example.com
  tags:
  - Keys
  properties:
  - type: OpenAPI
    url: openapi/sso-keys-api-openapi.yml
  - type: Documentation
    url: https://www.oasis-open.org/standards#samlv2.0
  - type: Documentation
    url: https://wiki.oasis-open.org/security/FrontPage
  - type: Documentation
    url: https://openid.net/connect/
  - type: Specification
    url: https://openid.net/developers/specs/
- aid: sso:sso-logout-api
  name: SSO Logout API
  description: SAML 2.0 Single Logout (SLO) endpoints for terminating SSO sessions across all service providers.
  humanURL: https://www.oasis-open.org/standards#samlv2.0
  baseURL: https://your-idp.example.com
  tags:
  - Logout
  properties:
  - type: OpenAPI
    url: openapi/sso-logout-api-openapi.yml
  - type: Documentation
    url: https://www.oasis-open.org/standards#samlv2.0
  - type: Documentation
    url: https://wiki.oasis-open.org/security/FrontPage
  - type: Documentation
    url: https://openid.net/connect/
  - type: Specification
    url: https://openid.net/developers/specs/
- aid: sso:sso-metadata-api
  name: SSO Metadata API
  description: SAML 2.0 metadata endpoints for exchanging federation configuration between identity providers and service
    providers.
  humanURL: https://www.oasis-open.org/standards#samlv2.0
  baseURL: https://your-idp.example.com
  tags:
  - Metadata
  properties:
  - type: OpenAPI
    url: openapi/sso-metadata-api-openapi.yml
  - type: Documentation
    url: https://www.oasis-open.org/standards#samlv2.0
  - type: Documentation
    url: https://wiki.oasis-open.org/security/FrontPage
  - type: Documentation
    url: https://openid.net/connect/
  - type: Specification
    url: https://openid.net/developers/specs/
- aid: sso:sso-token-api
  name: SSO Token API
  description: Token endpoint operations for exchanging authorization codes and refresh tokens for access tokens and ID tokens.
  humanURL: https://www.oasis-open.org/standards#samlv2.0
  baseURL: https://your-idp.example.com
  tags:
  - Token
  properties:
  - type: OpenAPI
    url: openapi/sso-token-api-openapi.yml
  - type: Documentation
    url: https://www.oasis-open.org/standards#samlv2.0
  - type: Documentation
    url: https://wiki.oasis-open.org/security/FrontPage
  - type: Documentation
    url: https://openid.net/connect/
  - type: Specification
    url: https://openid.net/developers/specs/
- aid: sso:sso-user-info-api
  name: SSO User Info API
  description: UserInfo endpoint for retrieving authenticated user profile claims.
  humanURL: https://www.oasis-open.org/standards#samlv2.0
  baseURL: https://your-idp.example.com
  tags:
  - User Info
  properties:
  - type: OpenAPI
    url: openapi/sso-user-info-api-openapi.yml
  - type: Documentation
    url: https://www.oasis-open.org/standards#samlv2.0
  - type: Documentation
    url: https://wiki.oasis-open.org/security/FrontPage
  - type: Documentation
    url: https://openid.net/connect/
  - type: Specification
    url: https://openid.net/developers/specs/
common:
- type: AgenticAccess
  url: agentic-access/sso-agentic-access.yml
- type: DomainSecurity
  url: security/sso-domain-security.yml
- type: Authentication
  url: authentication/sso-authentication.yml
- url: https://www.oasis-open.org/standards#samlv2.0
  type: Specification
- url: https://openid.net/connect/
  type: Specification
- url: https://oauth.net/2/
  type: Specification
- url: https://github.com/api-evangelist/sso
  type: GitHubOrg
- url: json-ld/sso-context.jsonld
  type: JSONLD
- url: json-schema/sso-saml-assertion-schema.json
  type: JSONSchema
- url: json-schema/sso-oidc-token-schema.json
  type: JSONSchema
- url: vocabulary/sso-vocabulary.yml
  type: Vocabulary
- url: rules/sso-rules.yml
  type: SpectralRules
- url: https://www.oasis-open.org/feed/
  type: Blog