# Auth.md

TTS Library's API (`/api/voices`, `/api/metadata`, `/api/audio-url`) and MCP server (`/api/mcp`) are **public and read-only**. There is no write access, no user accounts, and no protected data - every response is derived from the public voice catalog at [ttslibrary.com](https://ttslibrary.com). This document follows the [auth.md](https://workos.com/auth-md) convention so an agent can confirm that in one request, instead of guessing.

## Discover

Machine-readable confirmation that no authentication is required: [/.well-known/oauth-protected-resource](https://ttslibrary.com/.well-known/oauth-protected-resource) (RFC 9728). It declares an empty `authorization_servers` list because there is no `agent_auth` block to advertise - no `register_uri`, no token issuer.

## Pick a method

There is only one method: **none**. Send requests directly; no `identity_assertion`, API key, or bearer token is expected or checked.

## Register

Not applicable - there is no `register_uri` because there is nothing to register for. Any client can call the API immediately.

## Claim

Not applicable - there is no credential to claim, so there is no `claim_uri`.

## Use the credential

Not applicable. Requests need no `Authorization` header. You will not receive a `401` with a `WWW-Authenticate` challenge on these endpoints, because nothing is gated.

## Errors

Errors are returned as `{ "error": { "code": "...", "message": "..." } }` with a standard HTTP status (`400` for bad input, `429` for rate limiting with a `Retry-After` header, `500` for server errors). None of these relate to authentication - see [/openapi.json](https://ttslibrary.com/openapi.json) for the full error model.

## Revocation

Not applicable - there is no `revocation_uri` because there is no credential to revoke.

## Rate limits

Requests are rate-limited per IP; see the `X-RateLimit-*` response headers on any API response for current limits.

## Contact

Questions: [andrewm@telnyx.com](mailto:andrewm@telnyx.com) or see [/contact](https://ttslibrary.com/contact).