# Clerk

**Canonical:** https://apis.io/providers/clerk-dev/  
**Website:** https://clerk.com/  
**APIs profiled:** 15

Clerk is a complete authentication and user management platform for web and mobile apps, providing embeddable UI components, SDKs, and REST APIs to handle sign-up and sign-in, users, organizations and memberships, sessions, multi-factor authentication, JWTs and JWT templates, JWKS, SAML/enterprise SSO, OAuth applications, and email/SMS verification. The Clerk Backend API (base https://api.clerk.com/v1, secret-key authenticated) manages these resources server-side, the Frontend API drives client auth flows, and change events are delivered as Svix-powered HTTP webhooks.

## Kin Score — 37.7 / 100 (thin)

Scored 2026-08-24 under rubric 0.13.0. Trend: flat (-0.4 from 38.1).

| Facet | Score |
|---|---|
| Discoverability | 74.1 |
| Contract Quality | 52.7 |
| Governance | 0.0 |
| Contract Governance | 0.0 |
| Operational Transparency | 34.2 |
| Developer Ergonomics | 23.8 |
| Commercial Clarity | 39.5 |
| Access Clarity | 39.5 |

## Agent readiness — 19.8 (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 | no |
| Dry Run Mode | no |
| Delegated Identity | no |
| Protected Resource Metadata | no |
| Dynamic Client Registration | no |
| Agentic Commerce | no |

## Access

Freemium · Self-serve signup — onboarding: self-serve, pricing: freemium, trial: no (confidence: high).

## APIs (15)

- **Clerk Allowlist & Blocklist API** — Identifiers permitted or denied from signing up.
- **Clerk Clients API** — Browser / device clients tracking active sessions.
- **Clerk Email & SMS API** — Email addresses, phone numbers, and message templates.
- **Clerk Invitations API** — Application-level sign-up invitations.
- **Clerk JWKS API** — Public keys for verifying Clerk-issued JWTs.
- **Clerk JWT Templates API** — Named claim templates for custom session tokens.
- **Clerk OAuth Applications API** — OAuth applications where Clerk is the identity provider.
- **Clerk Organization Invitations API** — Invitations to join an organization.
- **Clerk Organization Memberships API** — Members of an organization and their roles.
- **Clerk Organizations API** — Multi-tenant organizations.
- **Clerk SAML & Enterprise Connections API** — Enterprise SSO connections.
- **Clerk Sessions API** — User sessions and session tokens.
- **Clerk Sign-ups & Tokens API** — Sign-up attempts, sign-in tokens, and actor tokens.
- **Clerk Users API** — Create and manage users and their identities.
- **Clerk Webhooks API** — Svix-powered webhook portal management.

## Agentic access (1)

- **Clerk Dev Agentic Access** — 80 operations · 54 acting · 5 human-in-the-loop

## Security (3)

- **Clerk Dev Authentication** — http · 1 scheme
- **Clerk Dev Domain Security** — TLSv1.3 · HSTS · DMARC
- **Clerk Dev Vulnerability Disclosure** — security.txt · contact published

## Plans (1)

- **Clerk Dev Plans Pricing**

## Tags

Authentication, User Management, Identity, Sessions, Organization, SSO, JWT, MFA

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