Seven findings from the latest review on #758 (3 medium, 4 low/nit):
Medium:
- storage.py: replace 5 ``assert self.cipher is not None`` sites with
explicit ``RuntimeError`` so missing TOKEN_ENCRYPTION_KEY can't silently
become an AttributeError under ``python -O``
- session_backend.py: document the silent-invalidation invariant —
refresh-token TTL expiry without explicit logout deliberately makes
the browser session unusable; future readers must not relax it
- server/oauth_tools.py: drop user_id from the Flow 2 session_id
identifier — use ``flow2_{secrets.token_hex(16)}`` so audit logs and
DB rows don't carry user_id in the session_id field
Low / nit:
- token_utils.py: drop _fetch_locks dict entry in finally so a probed
deployment can't grow the lock dict without bound; coalescing test
now pins the invariant with len(_fetch_locks) == 0
- browser_oauth_routes.py: strip trailing slash from settings.nextcloud_host
before constructing the well-known URL so a host configured as
``https://cloud.example.com/`` doesn't produce a double-slash
- browser_oauth_routes.py: add comment explaining the three-layer CSRF
policy on the mcp_session cookie set (SameSite=Lax + POST-only logout
+ Origin/Referer check)
- oauth_routes.py: convert all 23 f-string log calls to lazy %-style
per the CLAUDE.md / memory feedback_lazy_logging convention
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>