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

# User Passkey Registered

The `user.passkey.registered` event is triggered when a user successfully completes the WebAuthn registration ceremony and a new passkey credential is stored against their account.

Use this event to drive a "we added a new passkey to your account — wasn't you?" security notification. The webhook payload carries the credential's nickname, transports, and backup state so the email or in-app banner can identify which device was added without exposing internal identifiers.

Idempotent re-registration (the user retries the same authenticator and the server short-circuits on the duplicate-credential check) does **not** re-emit the event.

## Event payload