Stack Auth

Stack Auth is an open-source authentication and user management platform positioned as a self-hostable alternative to closed-source providers like Clerk and Auth0. It bundles password, OAuth / SSO, and two-factor sign-in flows with organizations, teams, role-based access control, impersonation, webhooks, and pre-built UI components built on shadcn/ui (or a headless SDK). Stack Auth is available as a hosted SaaS at app.stack-auth.com and as a self-hosted deployment from the stack-auth/stack monorepo on GitHub. Authentication is JWT-based. Y Combinator-backed.

Stack Auth publishes 13 APIs on the APIs.io network, including Auth API, Connected Accounts API, Contact Channels API, and 10 more. Tagged areas include Authentication, User Management, Open-Source, Self-Hosted, and Identity.

Stack Auth’s developer surface includes authentication, documentation, GitHub presence, pricing, engineering blog, and 6 more developer resources.

🌐 Visit website 📡 Source on GitHub

27.7/100 thin ▼ -9.0 Agent 21/100 agent aware Full breakdown ↓
scored 2026-08-25 · rubric v0.14.0

18 APIs

Authentication User Management Open-Source Self-Hosted Identity Organization RBAC

Kin Score

Kin Score How this is scored →
scored 2026-08-25 · rubric v0.14.0

Composite quality — 27.7/100 · thin

Contract Quality 3.5 / 25

Developer Ergonomics 4.8 / 20

Access Clarity 7.9 / 20

Operational Transparency 3.4 / 13

Contract Governance 0.0 / 12

Discoverability 8.2 / 10

Agent readiness — 21/100 · agent aware

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 0 / 8

Request/Response Examples 0 / 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 8 / 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 Surface 0 / 5

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/stack-auth: 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 18

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

Open Collections 15

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

Rate Limits 1

Documented rate limits and quota policies.

Stack Auth Rate Limits

2 limits

RATE LIMITS

FinOps 1

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

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

LlmsText

LlmsText

Build 1

SDKs, sample code, and the tooling you integrate with

GitHub

GitHub

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Commercial 1

Pricing, plans, and the legal terms of use

Pricing

Pricing

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 2

Properties that don't map to a standard resource type

AgentCard

AgentCard

Dashboard

Dashboard

Source (apis.yml)

aid: stack-auth
url: https://raw.githubusercontent.com/api-evangelist/stack-auth/refs/heads/main/apis.yml
name: Stack Auth
kind: company
description: Stack Auth is an open-source authentication and user management platform positioned as a self-hostable alternative
  to closed-source providers like Clerk and Auth0. It bundles password, OAuth / SSO, and two-factor sign-in flows with organizations,
  teams, role-based access control, impersonation, webhooks, and pre-built UI components built on shadcn/ui (or a headless
  SDK). Stack Auth is available as a hosted SaaS at app.stack-auth.com and as a self-hosted deployment from the stack-auth/stack
  monorepo on GitHub. Authentication is JWT-based. Y Combinator-backed.
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
tags:
- Authentication
- User Management
- Open-Source
- Self-Hosted
- Identity
- Organization
- RBAC
tags_raw:
- Authentication
- User Management
- Open Source
- Self-Hosted
- Identity
- Organizations
- RBAC
created: '2026-05-23'
modified: '2026-05-23'
specificationVersion: '0.23'
apis:
- aid: stack-auth:rest-api
  name: Stack Auth REST API
  description: REST API for managing users, sessions, OAuth providers, teams, organizations, permissions, and webhooks. Used
    by Stack Auth's own SDKs and available for custom backend integrations. JWT-based authentication with server / publishable
    / secret API keys per project.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - REST
  - Authentication
  - User
  - Team
  tags_raw:
  - REST
  - Authentication
  - Users
  - Teams
  properties:
  - type: Documentation
    url: https://docs.stack-auth.com/rest-api/overview
- aid: stack-auth:webhooks
  name: Stack Auth Webhooks
  description: Outbound webhook events for user lifecycle, team / organization membership, and permission changes. Customers
    register endpoint URLs and verify delivery via signed payloads.
  humanURL: https://docs.stack-auth.com/concepts/webhooks
  baseURL: customer-configured
  tags:
  - Webhook
  - Event
  tags_raw:
  - Webhooks
  - Events
  properties:
  - type: Documentation
    url: https://docs.stack-auth.com/concepts/webhooks
- aid: stack-auth:sdk-react
  name: Stack Auth React / Next.js SDK
  description: Frontend SDK distributed as @stackframe/stack on npm. Provides React components, hooks, and Next.js App Router
    middleware for sign-in, sign-up, account settings, and team / organization management. Headless mode supported for custom
    UI.
  humanURL: https://docs.stack-auth.com/sdk/overview
  baseURL: https://github.com/stack-auth/stack
  tags:
  - SDK
  - React
  - Next.js
  - Frontend
  properties:
  - type: Documentation
    url: https://docs.stack-auth.com/sdk/overview
  - type: Repository
    url: https://github.com/stack-auth/stack
- aid: stack-auth:cli
  name: Stack Auth CLI
  description: Project bootstrap CLI distributed as @stackframe/init-stack on npm, invoked with `npx @stackframe/init-stack@latest`
    to wire Stack Auth into a new or existing project.
  humanURL: https://docs.stack-auth.com/getting-started/setup
  baseURL: https://github.com/stack-auth/stack
  tags:
  - CLI
  - Tooling
  properties:
  - type: Documentation
    url: https://docs.stack-auth.com/getting-started/setup
- aid: stack-auth:self-hosted
  name: Stack Auth Self-Hosted (stack-auth/stack)
  description: Open-source monorepo containing the Stack Auth backend (Next.js + Postgres) and dashboard. Deployable on customer
    infrastructure as an alternative to the hosted SaaS at app.stack-auth.com.
  humanURL: https://github.com/stack-auth/stack
  baseURL: https://github.com/stack-auth/stack
  tags:
  - Open-Source
  - Self-Hosted
  - Repository
  tags_raw:
  - Open Source
  - Self-Hosted
  - Repository
  properties:
  - type: Repository
    url: https://github.com/stack-auth/stack
- aid: stack-auth:stack-auth-auth-api
  name: Stack Auth Auth API
  description: The Auth API from Stack Auth — 4 operation(s) for auth.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Authentication
  tags_raw:
  - Auth
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-auth-api-openapi.yml
- aid: stack-auth:stack-auth-connected-accounts-api
  name: Stack Auth Connected Accounts API
  description: The Connected Accounts API from Stack Auth — 1 operation(s) for connected accounts.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Connected Accounts
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-connected-accounts-api-openapi.yml
- aid: stack-auth:stack-auth-contact-channels-api
  name: Stack Auth Contact Channels API
  description: The Contact Channels API from Stack Auth — 4 operation(s) for contact channels.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Contact Channels
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-contact-channels-api-openapi.yml
- aid: stack-auth:stack-auth-emails-api
  name: Stack Auth Emails API
  description: The Emails API from Stack Auth — 2 operation(s) for emails.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Emails
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-emails-api-openapi.yml
- aid: stack-auth:stack-auth-sessions-api
  name: Stack Auth Sessions API
  description: The Sessions API from Stack Auth — 3 operation(s) for sessions.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Sessions
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-sessions-api-openapi.yml
- aid: stack-auth:stack-auth-stack-auth-rest-api-api
  name: Stack Auth Stack Auth REST API API
  description: The Stack Auth REST API API from Stack Auth — 1 operation(s) for stack auth rest api.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Stack Auth REST API
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-stack-auth-rest-api-api-openapi.yml
- aid: stack-auth:stack-auth-team-api-keys-api
  name: Stack Auth Team Api Keys API
  description: The Team Api Keys API from Stack Auth — 3 operation(s) for team api keys.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Team Api Keys
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-team-api-keys-api-openapi.yml
- aid: stack-auth:stack-auth-team-memberships-api
  name: Stack Auth Team Memberships API
  description: The Team Memberships API from Stack Auth — 1 operation(s) for team memberships.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Team Memberships
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-team-memberships-api-openapi.yml
- aid: stack-auth:stack-auth-team-permissions-api
  name: Stack Auth Team Permissions API
  description: The Team Permissions API from Stack Auth — 1 operation(s) for team permissions.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Team Permissions
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-team-permissions-api-openapi.yml
- aid: stack-auth:stack-auth-teams-api
  name: Stack Auth Teams API
  description: The Teams API from Stack Auth — 2 operation(s) for teams.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Team
  tags_raw:
  - Teams
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-teams-api-openapi.yml
- aid: stack-auth:stack-auth-user-api-keys-api
  name: Stack Auth User Api Keys API
  description: The User Api Keys API from Stack Auth — 3 operation(s) for user api keys.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - User Api Keys
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-user-api-keys-api-openapi.yml
- aid: stack-auth:stack-auth-users-api
  name: Stack Auth Users API
  description: The Users API from Stack Auth — 2 operation(s) for users.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - User
  tags_raw:
  - Users
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-users-api-openapi.yml
- aid: stack-auth:stack-auth-webhooks-api
  name: Stack Auth Webhooks API
  description: The Webhooks API from Stack Auth — 1 operation(s) for webhooks.
  humanURL: https://docs.stack-auth.com/rest-api/overview
  baseURL: https://api.stack-auth.com
  tags:
  - Webhook
  tags_raw:
  - Webhooks
  properties:
  - type: OpenAPI
    url: openapi/stack-auth-webhooks-api-openapi.yml
common:
- type: AgentCard
  url: a2a/stack-auth-a2a.yml
  name: A2A Agent Card
  description: Agent Card served at /.well-known/agent-card.json (flavored against A2A 1.0.0).
- type: AgenticAccess
  url: agentic-access/stack-auth-agentic-access.yml
- type: DomainSecurity
  url: security/stack-auth-domain-security.yml
- type: Authentication
  url: authentication/stack-auth-authentication.yml
- type: Website
  url: https://stack-auth.com/
- type: Documentation
  url: https://docs.stack-auth.com/
- type: GitHub
  url: https://github.com/stack-auth
- type: Dashboard
  url: https://app.stack-auth.com/
- type: Pricing
  url: https://stack-auth.com/pricing
- type: Blog
  url: https://stack-auth.com/blog
- type: LlmsText
  url: https://docs.stack-auth.com/llms.txt
integrations:
- name: Next.js
- name: React
- name: shadcn/ui
- name: PostgreSQL
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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