# 42min — API

> The 42min Public REST API, covering authentication (PATs, OAuth 2.1 + PKCE), scopes, rate limits, idempotency, optimistic locking, and a full reference for every /v1 endpoint.

This file indexes the API section of the 42min Help Center. Each linked page is also available
as raw markdown at the same URL with a `.md` suffix.
The full text of this section is at https://42min.us/help/api/llms-full.txt
The whole Help Center is at https://42min.us/help/llms.txt
The whole site is at https://42min.us/llms.txt

- [API overview](https://42min.us/help/api/overview): The 42min Public REST API, its base URL, JSON envelopes, and what you can do with it.
- [Authentication](https://42min.us/help/api/authentication): Authenticate to the 42min API with a personal access token, or with an OAuth 2.1 + PKCE access token. Includes the full authorize → consent → token → refresh flow with reuse detection.
- [Scopes](https://42min.us/help/api/scopes): The full list of OAuth and PAT scopes, what each one grants, the alias expansions, and how scope enforcement works.
- [Rate limits](https://42min.us/help/api/rate-limits): Per-minute request quotas, the X-RateLimit-* headers, and how to back off on 429.
- [Idempotency](https://42min.us/help/api/idempotency): How the Idempotency-Key header makes write requests safe to retry, with fingerprinting, replay window, and conflict handling.
- [Optimistic locking (ETag / If-Match)](https://42min.us/help/api/optimistic-locking): How PATCH on /v1/bookings uses ETag and If-Match for optimistic concurrency control, giving read-modify-write without races.
- [Errors](https://42min.us/help/api/errors): The error envelope, the code taxonomy, and what each status means.
- [Discovery](https://42min.us/help/api/discovery): The .well-known endpoints that publish the OAuth authorization server and protected resource metadata.
- [GET /v1/_ping](https://42min.us/help/api/ping): Cheap auth/scope/identity probe — confirms your token reaches the API and reports who it belongs to.
- [GET /v1/me](https://42min.us/help/api/me): Return the profile of the user the token authenticates.
- [/v1/event-types](https://42min.us/help/api/event-types): List and read event types in the authenticated account.
- [/v1/slots](https://42min.us/help/api/slots): List available slots for an event type over a window, and check whether a specific slot is bookable right now.
- [/v1/bookings](https://42min.us/help/api/bookings): List, read, create, cancel, reschedule, and patch bookings. The write-heavy surface, where every mutation needs an Idempotency-Key and PATCH needs an If-Match ETag.
- [/v1/series](https://42min.us/help/api/series): List, read, create, and manage recurring meeting series. Pause, resume, end, edit the pattern, or change the host, with the same idempotency and optimistic-locking rules as bookings.
- [/v1/webhooks](https://42min.us/help/api/webhooks): Manage webhook subscriptions over the API, so you can create, list, edit, delete, rotate the signing secret, send a test, and read recent deliveries. Each credential gets its own sandbox.