Confidence envelope
ZIP-mode and SST lookups return a top-level confidence field with
one of four coarse buckets:
| Level | What it means | What to do |
|---|---|---|
exact | Rooftop precision (address-mode or ZIP+4 boundary file) | Trust the rate |
high | Address resolved by state DoR locator | Trust the rate |
medium | ZIP-centroid resolution; rate is the most common for that ZIP | Surface the rate; consider re-querying in address mode for high-value transactions |
low | Best-guess answer (rare; usually means coverage gap) | Don’t auto-bill — surface to a human |
The confidence is independent of the response’s row_count — a
“medium”-confidence response can have one row (the ZIP didn’t
straddle anything) or multiple (it did). Check both.
Address-mode lookups via TX Comptroller’s Mulesoft locator omit
confidence because the locator yields an authoritative
single-jurisdiction answer.
Full content coming soon.