Which defects should a sample library cover when buying a commercial vision inspection system?

For a commercial vision inspection system, build the sample library from actual production defects: missing pieces, surface damage, contamination, dimensional faults and color deviations. Have the supplier run representative material and log process data, capturing both average results and abnormal samples, since a strong average can mask unstable operation. Tie each acceptance requirement to a measured outcome instead of a simple pass mark. When models look similar, compare measured application data rather than motor power or nominal speed.