Passkey-first, passwordless authentication with automatic fallback to magic link and email OTP — plus TOTP, backup codes, SMS OTP, and BYOAM for step-up and custom flows. Everything below is real, live-verified content: no placeholder pages, no "coming soon" sections.
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Quickstart
Install → initialize → a real, working login. One canonical path, zero prior context needed.
Passkey
WebAuthn / biometric sign-in, the default first step of the fallback cascade.
Magic Link
Passwordless email link — the first real fallback after passkey.
Email OTP
A 6-digit code by email. Works with zero dashboard setup — the Quickstart's first example.
TOTP
Authenticator-app step-up for an already-signed-in user.
Backup Codes
Single-use recovery codes for when a primary factor is unavailable.
SMS OTP
A 6-digit code by SMS. Implementation complete — real current sending status disclosed on the page.
Core Concepts
Passkey-first fallback, environments, external user ID bridging, and BYOAM — the model everything else assumes.
Dashboard Guide
What every real dashboard page does — Users, Monitoring, Configuration, Playground, Billing.
SDK Reference
Every real public method on the current published @threshold1/auth, generated from the actual package.
API Reference
Raw HTTP calls for every method, for stacks without a JS SDK.
Webhooks Reference
All 11 real event types, payload shapes, signature verification, and retry behavior.
Error Reference
Every business-logic and auth-layer error code — real HTTP status, what it means, what to do.
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