OAuth 2.0 PKCE web login
Prompt
Create a sequence diagram for OAuth 2.0 PKCE login with browser, frontend app, authorization server, session store, and resource API. Show authorization request, redirect back with code, code exchange, session creation, access token validation, refresh token rotation, and expired refresh token path.
Why this prompt works
It names the real participants and includes the token lifecycle details engineers usually need to review.
Follow-up prompt
Add MFA after primary login and show how logout invalidates both session and refresh token.