CAM — Collector / Adaptor / Monitor

Template for judgment gates: systems that periodically gather evidence, make one decision, and measure whether it worked. Three tiers, strict writer roles, one append-only ledger keyed scope × round. The ledger IS the audit trail — no side-channel state.

sources ──▶ collectors (N, read wide, cheap) ──append evidence rows──▶ ┐
                                                                       │
        adaptor (1, smart) ◀── reads evidence ─────────────────────────┤  ONE append-only ledger
            │ appends ONE decision row + makes ONE narrow write        │  keyed scope × round
            ▼                                                          │
        monitor (script; model only on anomaly) ──measurement rows──▶  ┘
                                          any tier may append a HALT row

When NOT to use

CAM = checklist + ledger + clock. The pre-op checklist / post-op confirmation skeleton is the commodity core; CAM earns its complexity only via: