# Review by Principal Systems Engineer (Google/Stripe caliber) (Round 3)

VERDICT: approve

FINDINGS:
- [src/colonyos/daemon.py:_ensure_daily_thread]: Double-call from _tick and _ensure_notification_thread is safe (short-circuits) but implicit — a comment would help
- [src/colonyos/daemon.py:_create_daily_summary]: Filters by added_at date, not completion date — reasonable V1 trade-off, should be documented
- [src/colonyos/slack.py:format_daily_summary]: Unsanitized mrkdwn interpolation of user-controlled fields — pre-existing pattern, low risk
- [src/colonyos/daemon.py:_ensure_daily_thread]: Lock scope covers state mutation only, not the full create+persist sequence — safe given single-threaded tick loop
- [src/colonyos/daemon.py:630]: Budget exhaustion correctly elevated to critical=True (fix iteration 2)

SYNTHESIS:
This is a clean, well-scoped implementation that correctly identifies and modifies the two chokepoints (`_post_slack_message` and `_ensure_notification_thread`) without touching the downstream `SlackUI`/`FanoutSlackUI` machinery. The `critical=True` parameter makes the safety invariant — critical alerts are never buried in a thread — explicit and auditable at each call site. The hour-aware rotation logic, restart recovery via `DaemonState` persistence, and graceful degradation on Slack API failures are all correct. The `_post_slack_message` consolidation from inline token lookup to `_get_notification_client()` is a net reliability improvement, reducing the token acquisition surface to one code path. Fix iteration 2 properly addressed the two outstanding concerns: budget exhaustion alerts elevated to `critical=True` and rotation audit trail logging added. From a systems reliability perspective, the blast radius is well-contained — the worst case on any failure path is a top-level Slack message (the pre-existing behavior), never a lost notification. All 55 new tests pass, covering config, state, lifecycle, routing, summary generation, integration, and backward compatibility. The five non-blocking findings are all appropriate for follow-up iterations. Ship it.

Review artifact written to `cOS_reviews/reviews/principal_systems_engineer_google_stripe_caliber/20260401_round1_you_are_sending_too_many_slack_messages_to_the_m_1b324759d9.md`.