EXAMPLES · UPDATED 10 OCTOBER 2026
BOM rule examples
Product experts already know when a part is needed. These examples show that knowledge written as rules, and exactly what each rule does to a unit’s bill of materials.
The examples use a fictional frame kit. Your rules use your own fields, components and tables.
What a rule can do
In FactorySpec, a plain English condition becomes a precise rule over the inputs you have declared. Each rule has a fixed job:
- Include a BOM line, such as a support or extra fixings.
- Block a combination that cannot be made, with a reason.
- Allow an option only in the right circumstances.
- Make a field apply only when another choice needs it.
Quantities, calculations and components belong to the reviewed model. A rule decides when they apply; it does not invent them.
Rules that include parts
“Add a centre support when the finished width is more than 1,200 mm.”
1,200.1 mm wide: a support cut to the width less 40 mm, two clips and four screws are added. Exactly 1,200 mm wide: none of them.
“Include the panel when a panel type is chosen.”
With a panel: one panel at the width less 60 mm by the height less 60 mm. Without: no panel line at all, rather than a line with a count of zero.
Rules that block
“Black frames cannot take a clear panel.”
The unit is refused with that reason, and no bill of materials is produced. Change the finish or the panel and evaluate again.
“Panels are not available on frames narrower than 400 mm.”
A 350 mm frame with a panel is refused before any parts are listed.
Rules that shape the choices
“Offer the clip-on cover only for the Classic range.”
Other ranges never allow the option, so it cannot be chosen by mistake.
“Ask for the panel colour only when a panel is chosen.”
Without a panel, no colour is needed. A colour left over from an earlier choice has to be cleared, not silently ignored.
From plain English to an approved rule
- Describe the condition in plain English for one rule in the model.
- SmartFACT proposes a precise condition over your field list. Only that list and your request are sent to the AI model, never customer records.
- Anything ambiguous or unsupported is shown back, and you are asked for a narrower rule.
- Adopting the proposal creates an ordinary draft, which needs worked examples and an independent review like any other change.
- Once released, the rule runs exactly as approved, with no AI call when units are evaluated.
What rules cannot do
- Write formulas or quantities: those are set in the model.
- Search for a combination that works: evaluation runs forwards from the inputs.
- Decide whether a new design is safe: that stays with your engineers.
Read next
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