> ## Documentation Index
> Fetch the complete documentation index at: https://developers.loyaltylion.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

The LoyaltyLion API supports two recommended methods of authentication - API keys and OAuth, and one deprecated method, token & secret.

<Card title="API keys" icon="key" href="/api-reference/authentication/api-keys">
  Merchants can create API keys to authenticate requests to the LoyaltyLion API.
  Each API key has a unique token, set of permissions (scopes) and can be
  disabled or deleted at any time.
</Card>

<Card title="OAuth" icon="link" iconType="solid" href="/api-reference/authentication/oauth">
  If you're a LoyaltyLion partner, OAuth is the recommended method of accessing
  our API. It provides the best experience for merchants as they don't need to
  manage API keys manually.
</Card>

<Card title="Token and secret (deprecated)" icon="lock" href="/api-reference/authentication/token-secret">
  Each LoyaltyLion site has a single token and secret which can be used to
  authenticate API requests. This method of authentication is deprecated and
  will be removed in future, because it doesn't support permissions or
  credential rotation.
</Card>