BOM Cost Review Skill

A BOM is a list of promises: that each part will be buyable, at that price, at your volume, for the life of the product. This skill reviews a BOM the way a sourcing veteran does — Pareto the cost, flag the single-source and end-of-life traps before they become line-down events, and separate real cost-down candidates from wishful thinking.

What This Skill Produces

• A cost rollup by commodity class with % of total
• Top-10 cost drivers (they usually carry 70–80% of BOM cost)
• Risk flags per line: single-source, lifecycle (EOL/NRND), MOQ mismatch, long lead time
• A prioritised cost-down candidate list with realistic savings and effort
• Tariff and logistics sensitivity notes

Required Inputs

Ask for these if not provided; work with a partial BOM if that's all there is, labelling gaps [missing — request from EE/sourcing]:

• The BOM — part numbers, descriptions, quantities, unit costs (any format; structure it)
• Annual forecast volume — needed for MOQ math and price-break realism
• Target BOM cost — what "good" looks like
• Sourcing detail if available — approved vendors, country of origin, lead times, lifecycle status
• Product stage — EVT-stage BOMs get design-out suggestions; MP-stage BOMs get negotiation/resourcing ones

Review Framework

1. Rollup. Group into commodity classes (PCBA/semiconductors, passives, display, battery, mechanicals/enclosure, cables & connectors, packaging & accessories). Show cost and % per class, and total vs target with the gap.

Rank the top-10 lines by extended cost (unit × qty). Everything after these is noise until the big ten are handled.