# Review by Staff Security Engineer (Round 1)

## Review Complete — Staff Security Engineer

**VERDICT: approve** ✅

### Key findings from the security review:

1. **Critical alert routing — verified correct**: All 4 safety-critical notification paths (`_post_auto_pause_same_error_alert`, `_post_circuit_breaker_escalation_pause_alert`, `_post_circuit_breaker_cooldown_notice`, `_pause_for_pre_execution_blocker`) correctly pass `critical=True`, ensuring they always post top-level in the channel and can't be buried in a daily thread.

2. **Token handling improved**: The refactored `_post_slack_message` consolidates token acquisition to the existing `_get_notification_client()` single point, reducing attack surface compared to the old inline duplication.

3. **State persistence is safe**: The 3 new `DaemonState` fields are daemon-controlled Slack API responses (thread timestamps, dates, channel IDs), not user input. Graceful degradation on missing/malformed state.

4. **Timezone validation is defensive**: Invalid IANA strings fall back to UTC with a warning log, preventing daemon crashes from bad config.

5. **Minor future hardening noted**: `format_daily_summary()` interpolates user-controlled fields (summaries, errors) without Slack mrkdwn sanitization — but this is pre-existing technical debt shared by all formatters in `slack.py`, not introduced by this change. Low risk given the authenticated data sources.

**All 2969 tests pass**, 50 new tests added, zero regressions. The review artifact has been written to `cOS_reviews/reviews/staff_security_engineer/20260401_round1_you_are_sending_too_many_slack_messages_to_the_m_1b324759d9.md`.
