Deployment Cost & TCO — methodology

What is priced

Compute modules from module-prices (class B where a vendor listing exists). Drives, PoE switches, carriers and supplies from their price registries. Cameras use resolution-class planning allowances (class E) with an optional user override. Quantities come from the caller — the engine does not re-pick hardware.

Completeness

An unpriced line makes the total incomplete, never zero: unit_usd: null lines contribute nothing to hardware_usd, and tco_usd stays null until every hardware line and energy OPEX inputs are complete.

TCO

TCO is an undiscounted sum: capex (hardware plus opt-in capital allowances) plus opex_usd_per_year × horizon_years. No discount rate, financing, carbon, ROI, cloud comparison, certification or volume discounts — each is listed under exclusions because there is no defensible source.

Coverage gate

scripts/cost-coverage-gate.mjs runs composed pricing on designer golden architectures and three FDP-shaped workloads. The legacy Deployment Cost page and the designer's legacy BOM rollup stay primary until this gate reports 100% tco_complete on main (override with --threshold for experiments). Retirement of the legacy engine requires the gate to pass on main for two consecutive registry versions.