> ## Documentation Index
> Fetch the complete documentation index at: https://docs.0xkey.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Add an additional passkey

> Register an additional passkey credential for an existing user.

Additional passkeys are registered through WebAuthn after the user is authenticated. React Wallet Kit and `@0xkey-io/core` expose this via Auth Proxy and the public API.

<CardGroup cols={2}>
  <Card title="Passkeys" icon="fingerprint" href="/authentication/passkeys">
    Registration options and RPID requirements
  </Card>

  <Card title="React Wallet Kit" icon="react" href="/sdks/react/getting-started">
    Account settings and credential management UI
  </Card>

  <Card title="API — create authenticators" icon="book" href="/api-reference/activities/create-authenticators">
    `CREATE_AUTHENTICATORS` activity
  </Card>

  <Card title="Embedded Wallet Kit" icon="wallet" href="/reference/embedded-wallet-kit">
    Product overview
  </Card>
</CardGroup>