> For the complete documentation index, see [llms.txt](https://developers-apps-in-toss.toss.im/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers-apps-in-toss.toss.im/documentation/api-and-sdk-en/api/auth.md).

# Authentication

This explains the authentication methods for the Mini App partner server API.

All APIs identify the caller (the mini app) using an mTLS (mutual TLS) client certificate.

Because mTLS authentication takes place during TLS connection establishment, it does not appear in the request headers. As in the code examples (cURL, Python, Node.js) in each API document, you must include the issued certificate and private key file with the request.

Operational information such as firewall IP allowlists, mTLS certificate issuance and management, and request limits can be found in [Using the Server API](/documentation/api-and-sdk-en/integration/server-api.md) Please refer to the documentation.

For user-level APIs, depending on the endpoint, you must send one of the values below as well.

* `x-toss-user-key` Header — user key issued through Toss Login ([You can obtain it through](/documentation/api-and-sdk-en/common/authentication/toss-login.md#id-4) obtained via the API)
* `x-anon-key` Header — anonymous user identification key (Mini App SDK [User.getAnonymousKey](/documentation/api-and-sdk-en/common/authentication/hash-key.md) issued through the function)
* `Authorization: Bearer {accessToken}` Header — Toss Login Access Token ([Get AccessToken](https://developers-apps-in-toss.toss.im/documentation/api-and-sdk-en/api/pages/561ad5d7d159382ba4b3119d2a1d83daa77dd44e#id-2.-accesstoken) issued via the API, for some login APIs)


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