For each SKU, which competitor is suggested as a substitute, by which model, at what frequency. The Substitution Risk Matrix is one of the six PartSentinel deliverables — produced from specialised prompts (equivalent / cheaper / more available) on the audit panel.
A technician checks a compatibility via an AI assistant. The AI invents an equivalence that doesn't exist. Wrong part ordered. Failure. Return. Liability exposure. PartSentinel measures the rate of these invented substitutions per SKU per model — and stamps them with a court-admissible audit trail (revised Product Liability Directive, Dec. 2026).
Three prompt families: "What is an equivalent of X?", "What is a cheaper alternative?", "What is more available?". Each response is parsed for competitor brand, exact substitute SKU, and qualifier (validated / approximate / invented).
Which competitor is named, in which model, at which frequency.
Which exact SKU is suggested as the substitute — and whether it actually exists.
Frequency normalised across the panel — feeds the Substitution Risk Index.
Substitution Risk Matrix is delivered with the Quarterly tier. Mode 1 includes substitution counts; Mode 2 produces the per-SKU matrix.