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

# Overview

MoonKey one-time passcodes (OTP) allows you to streamline your authentication and onboarding by phone number via SMS or email.

Our flexible multi-identifier authentication API allows you to use the phone number either as your primary authentication identifier or secondary identifier.

<CardGroup cols={1}>
  <Card title="API Reference" icon="code" href="/api-reference/otps/create-email-otp" image="/images/conversion.png">
    One-time Passcodes (OTP) API
  </Card>
</CardGroup>

## Quickstart

<CardGroup cols={2}>
  <Card title="Integrate OTP SMS with Existing Auth flow" icon="lock-open" href="integrate-sms">
    Enable User login and signup by mobile phone numbers

    <br />

    <img src="https://mintcdn.com/streambird-23/PiBN7-K0u0e27Xai/images/otp-mfa-preview.png?fit=max&auto=format&n=PiBN7-K0u0e27Xai&q=85&s=7d256107913b8f03341a053b68def33f" width="512" height="178" data-path="images/otp-mfa-preview.png" />
  </Card>
</CardGroup>