Hub-and-spoke skill that converts "I need auth for app X" into a
reviewable plan across 5 phases: intake (flows/stack/storage/MFA),
identity-provider pick + env scaffold, session strategy + cookies,
authorization model + permission matrix, and threats + mitigations.
- 8 AskUserQuestion calls total (≥6 hub-and-spoke contract; 4 in Phase 1
+ 1 each in Phases 2–5).
- Reads all four _blocks/auth-*.md; never writes production code or
secret values.
- RULE 0.8 (Secrets SSoT): emits env VARIABLE NAMES only; storage path
is secrets/auth.env per domain-has-secrets.md.
- Constructor Pattern: 6 files, largest 115 LOC (<200 limit).
- Fail-closed default + NO DOWNGRADE on unsafe combinations
(passkey-only without recovery → return recovery-path options, not
"not supported").
Evidence grade [E2] — pipeline mirrors OWASP ASVS v4.0.3 chapters 2–4.
