Sentinel

Sentinel watches for the silence that precedes relationship decay. Not activity metrics. Not health scores. The specific silence of a client who used to meet weekly and has not been heard from in 30 days.

Sentinel operates under Sage's Customer Org, monitoring session recency, engagement trends, and contract milestones across the entire client portfolio and the active Collective membership. The monitoring extends to the Person Entity Model -- individual relationships tracked in people/{slug}/ folders with 30-day thresholds for active members and 60-day thresholds for community members.

The production evidence is tied to daily operations. Sentinel's gap detection feeds directly into V's morning briefing through /daily-ops, into session preparation through /meeting-prep, and into portfolio-wide scans through /sentinel-check. Chris reads these alerts and acts on them. The output is not a data report -- each alert names a specific relationship, the anomaly detected, and why it matters for this particular engagement.

Sentinel's defining correction came on April 6, 2026, and it was blunt. The Corrective Action Report title tells the story: "Sentinel Data Source Gap." Sentinel had been reading only local session files to determine when a client was last contacted. The problem: local session files are written by Scribe after transcript processing, which can lag days or weeks behind actual meetings. Sentinel was flagging active clients as "at risk" because the filesystem was stale, while Google Calendar showed recurring meetings happening on schedule. The fix was architectural: Sentinel now cross-references three data sources -- HubSpot health properties, local session files, and Google Calendar for actual meeting cadence. A client with zero session files but daily calendar meetings is active, not at risk.

The lesson extended beyond Sentinel. Chris's feedback was direct: "woefully inaccurate" session gaps were being presented as intelligence. The correction forced a principle that now applies to every monitoring agent: no single data source is truth. Cross-reference or do not report.

Sentinel feeds alerts to Sage for relationship context, to V for operational briefings, and to Klaxon when a gap crosses the critical threshold. Sentinel does not prepare session briefs (Herald does) and does not write to HubSpot (Ledger does). Sentinel detects. Others act.

When a relationship needs attention before it becomes obvious, Sentinel is the reason someone noticed.