---
updatedAt: 2025-06-17T07:36:46.000Z
agentTools:
  projectIndex: https://developers.happeo.com/llms.txt
---

# Authentication

What you need to know to authenticate to the api.

Happeo supports 2 types of authentication to the API:

* OAuth 2.0 with code challenge (PKCE)
* System Accounts

Choose the best method for you based on your use-case. Generally for any operations where you want the API access to act as the user, use OAuth 2.0. In cases where you want to act as a separate account or create a background thread, use a system account.