- session_id (clm_sess_...) in browser URL — identifies login attempt - user_code (ABCD-EFGH) visual confirmation — shown in both terminal and browser - device_code (secret) — CLI polls with this, never displayed - CLI accepts stdin paste of JWT token while polling (race) - Web page handles both ?session= and ?code= params Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>