Calculation Methodology
Calculations are classified as exact arithmetic, standardized-reference calculations, provider-specific calculations or production estimates.
Exact arithmetic
Conversions, percentages, dimensions and cost formulas return deterministic values from the inputs provided. Inputs, units and rounding rules are shown on the tool instead of being hidden behind a single unexplained answer.
Reference and provider rules
Rules such as KDP spine factors, GS1 barcode requirements or PDF production standards are tied to named sources and verification dates because external specifications can change. Provider-controlled rules are never presented as universal mathematics.
Estimates
Ink coverage, viewing-distance planning, waste, roll geometry and total-cost models are explicitly presented as estimates when real production conditions add variables the browser cannot observe.
File checks and uncertainty
Browser-side preflight distinguishes facts that can be detected locally from checks that need a full production preflight engine or the final output provider. An inconclusive browser check is labeled as such rather than being converted into a false pass.
Agent-readable access
The human interface remains the primary product. llms.txt and structured WebMCP annotations provide progressive, machine-readable discovery of the same calculators and references; they do not create separate hidden answers or different rules for AI systems.
Machine-readable references
llms.txt is the curated site map for language-model discovery. Focused Markdown references are published under /agent/ for preflight, resolution, sheet planning, costing, KDP, labels/packaging and decorated-print workflows. They link back to the human-facing tools instead of replacing them.