Editorial policy
The standards ImportCost applies to every published figure.
Primary sources only
A tariff figure is publishable only when it traces to a primary government document with a citation and a retrieval date. Secondary summaries may inform our understanding but are never the basis of a published number.
No generated facts
Language models are used, where used at all, to explain and to narrow candidates drawn from official data. They are never permitted to produce an HTS code, a duty rate, a legal authority, an effective date, or a fee. Any candidate presented to a reader maps to a record that exists in the imported dataset.
Dated, not evergreen
Tariff content is time-bound. Pages carry effective dates and, where a rule has lapsed, say so explicitly rather than quietly removing it. Historical rules are retained so that past entry dates still calculate correctly.
Uncertainty is published
Where scope is genuinely unresolved — a derivative-article list we have not imported, a two-tier action whose annex we have not parsed — the page says that, names what is missing, and links to the official source. We do not fill gaps with plausible defaults.