# Fido2

> FIDO2 passwordless authentication standard reference. Covers WebAuthn browser API, CTAP2 protocol, registration and authentication flows, passkey conditional UI, py_webauthn and SimpleWebAuthn server implementations, and Chrome DevTools testing.

- Skill: `bytesagain/fido2` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add bytesagain/fido2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/bytesagain/fido2/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Integrations & APIs
- Author: bytesagain (https://skillmd.com/u/bytesagain)
- Updated: 2026-09-21
- Page: https://skillmd.com/skills/bytesagain/fido2

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# FIDO2 Reference

Passwordless authentication standard.

## Commands

| Command | Description |
|---------|-------------|
| `intro` | Overview, authenticators |
| `webauthn` | Browser API, flows |
| `server` | Python/Node.js, testing |