Some rates cannot be settled from an HTS code, an origin and a date. Until now we picked a branch and served it at confidence 1.0 with no warning, which is the shape nobody thinks to report. /resolve and /resolve_batch now return a rate_conditional block on those lanes, naming what the answer turns on and what the other branch would be.
The live case is the ad valorem equivalent. Where a Section 301 floor or cap sits on a column 1 rate that is not ad valorem, U.S. note 52(k) makes the test a percentage of your entry's declared customs value, so two shipments of the same code at different values fall on opposite sides of the floor. Those lanes return reason: "ad_valorem_equivalent" with an AD_VALOREM_EQUIVALENT_REQUIRED warning and confidence 0.8. This is not a rare corner: 8.3% of general duties carry a per-unit term.
Read the bound before you total anything. The number on those lanes has not changed and it is a ceiling, not a certainty: where column 1 is a specific rate we net out nothing and charge the full floor, which over-states the duty. It is now marked rate_is_bound: "upper" instead of being served silently at full confidence. If you read only applicable_ad_valorem_rate you get exactly what you got before. Letting you pass the entered value on the request so we can compute the equivalent is the real fix and it is not built yet; tell us if you need it and it moves up.
The confidence reduction is its own named factor, rate_conditional, sitting beside base_rate rather than folded into the score, so you can see what cost you the 0.2.
A second reason, tariff_rate_quota, uses the same structure for in-quota versus over-quota. No lane emits it today. The textile and apparel quotas of the July 2026 forced-labor memo are directed but not established: USTR's own notice says it will establish them "when feasible", no Chapter 99 quota heading exists, and Bangladesh, Cambodia, Indonesia and Malaysia correctly carry the flat rate. Publishing in-quota alternatives now would headline a zero percent no importer can claim, so those four origins instead carry an info-severity TARIFF_RATE_QUOTA_DIRECTED warning with no confidence reduction. It flags a lane likely to move, not a doubt about today's number.
Additive. rate_conditional is always present and is null on almost every lane, and no existing field changed shape or meaning.