# Stack Auth

**Canonical:** https://apis.io/providers/stack-auth/  
**Website:** https://stack-auth.com/  
**APIs profiled:** 18

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.

## Kin Score — 27.7 / 100 (thin)

Scored 2026-08-25 under rubric 0.14.0. Trend: falling (-9.0 from 36.7).

| Facet | Score |
|---|---|
| Discoverability | 81.5 |
| Contract Quality | 13.8 |
| Governance | 0.0 |
| Contract Governance | 0.0 |
| Operational Transparency | 26.3 |
| Developer Ergonomics | 23.8 |
| Commercial Clarity | 39.5 |
| Access Clarity | 39.5 |

## Agent readiness — 21.2 (agent-aware)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | bearer |
| Idempotency | no |
| Error Semantics | no |
| OpenAPI Examples | no |
| Rate Limit Signal | documented |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | flavored |
| Dry Run Mode | no |
| Delegated Identity | no |
| Protected Resource Metadata | no |
| Dynamic Client Registration | no |
| Agentic Commerce | no |

## APIs (18)

- **Stack Auth REST API** — 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 integrati...
- **Stack Auth Webhooks** — Outbound webhook events for user lifecycle, team / organization membership, and permission changes. Customers register endpoint URLs and verify delivery via signed payloads.
- **Stack Auth React / Next.js SDK** — 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 / orga...
- **Stack Auth CLI** — 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.
- **Stack Auth Self-Hosted (stack-auth/stack)** — 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.stac...
- **Stack Auth Auth API** — The Auth API from Stack Auth — 4 operation(s) for auth.
- **Stack Auth Connected Accounts API** — The Connected Accounts API from Stack Auth — 1 operation(s) for connected accounts.
- **Stack Auth Contact Channels API** — The Contact Channels API from Stack Auth — 4 operation(s) for contact channels.
- **Stack Auth Emails API** — The Emails API from Stack Auth — 2 operation(s) for emails.
- **Stack Auth Sessions API** — The Sessions API from Stack Auth — 3 operation(s) for sessions.
- **Stack Auth Stack Auth REST API API** — The Stack Auth REST API API from Stack Auth — 1 operation(s) for stack auth rest api.
- **Stack Auth Team Api Keys API** — The Team Api Keys API from Stack Auth — 3 operation(s) for team api keys.
- **Stack Auth Team Memberships API** — The Team Memberships API from Stack Auth — 1 operation(s) for team memberships.
- **Stack Auth Team Permissions API** — The Team Permissions API from Stack Auth — 1 operation(s) for team permissions.
- **Stack Auth Teams API** — The Teams API from Stack Auth — 2 operation(s) for teams.
- **Stack Auth User Api Keys API** — The User Api Keys API from Stack Auth — 3 operation(s) for user api keys.
- **Stack Auth Users API** — The Users API from Stack Auth — 2 operation(s) for users.
- **Stack Auth Webhooks API** — The Webhooks API from Stack Auth — 1 operation(s) for webhooks.

## Agentic access (1)

- **Stack Auth Agentic Access** — 45 operations · 28 acting

## Security (2)

- **Stack Auth Authentication** — apiKey · 5 schemes
- **Stack Auth Domain Security** — TLSv1.3 · HSTS · DMARC

## Plans (1)

- **Stack Auth Plans Pricing**

## Tags

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

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/stack-auth/). Scores are computed from the provider's own public artifacts under a published rubric.