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

# Choose an Auth Method

The IDP SDK supports three end-user sign-in channels, but not every channel is
exposed the same way on every platform.

## OAuth

Use OAuth when users should sign in with a provider such as Google or another
configured IdP.

* available in Expo / React Native through `startOAuth()`
* available in browser apps through `createSwigWebClient()` and `redirectToOAuth()`
* supports provider discovery through `listProviders({ clientId })`

## Email OTP

Use email OTP when users should verify ownership of an email address without a
separate OAuth provider flow.

* available in Expo / React Native through `startEmailOtp()`
* the user enters the address and verification code inside the isolated host
* the host app does not receive the email address, OTP code, or callback JWT

## SMS OTP

Use SMS OTP when users should verify ownership of a phone number.

* available in Expo / React Native through `startSmsOtp()`
* the user enters the phone number and verification code inside the isolated host
* the host app does not receive the phone number, OTP code, or callback JWT

## Inputs you will see most often

Most auth starts are built around:

* `clientId`
* `policyId`
* `provider`
* `flow`

Most product flows use `flow: "role"` because the resulting callback carries
the Swig wallet and role context. The web start API also exposes
`flow: "session"`, but the primary documented path here is role-based auth.