Status: accepted

Accepted — merged with intent to implement.

RFC 0110: Name the §4.17 financial_validity entry's band "band"

Resolution

The UWMD maintainers accepted the member name band on 2026-10-21 to align §4.17 financial_validity[] with RFC 0109. The accepted scope also adds ltc to the metric list and removes stored entries marked info.

Summary

RFC 0109 made a financial-validity finding a deal flag with a band ("error" or "warning") and no severity, so no reader counts a weak deal as a defective record. Format §4.17 stores those flags in financial_validity[], but each entry still names the band severity, with values error | warning | info. This RFC renames the member to band, with the result's two values.

Motivation

• Two names for one fact. A fresh uwmd validate reports deal_flags[].band; the stored section reports financial_validity[].severity. A consumer reading both maps them by hand, which RFC 0108 removed for every other member of the section.
• The word RFC 0109 retired. severity is the member every reader counts as a defect. Keeping it on a stored deal flag reintroduces the misreading RFC 0109 was accepted to remove.
• info is not a band. Format §5.2 has warning and error columns only. The one corpus entry with info (Parkview, "LTV at 70.0% is at policy maximum but within range") records a value that crosses no band, so it is not a flag.

Proposed change

1. Format §4.17. A financial_validity[] entry carries band: "error" | "warning" in place of severity, with RFC 0109's meaning: the §5.2 column crossed. The §4.17 vocabulary note says so. overall_status still excludes the entries (RFC 0108, RFC 0109).
2. Metric vocabulary (D2). The entry's metric list gains ltc, the band RFC 0107 added.
3. No other member changes. flag_id, value, threshold, message, suppressed and suppress_reason keep their meaning.
4. Corpus. Every stored financial_validity[] entry renames severity to band. An entry whose value is info is not a deal flag and is removed (D3). The owner's same-evening ruling (3) regenerates the six stored sections from a fresh validate, so their entries already come from deal flags and none is info; the rename is then mechanical.

Compatibility analysis

No compatibility path (prelaunch; no 5.0 before launch). No implementation reads the section's contents, so nothing breaks at runtime. There is no section schema. A retired severity member is not refused, as RFC 0108 D5 did for the section's other retired spellings.

Conformance impact

The examples and fixtures that state the section (the six RFC 0108 files) rename the member. The 02-full-multifamily.parsed.json baseline follows its fixture. No other expected output changes.

Reference implementation

• Files: spec/UW_FORMAT_SPEC.md §4.17 and the corpus files above.
• API surface: none.

Alternatives considered

• Keep severity, restrict it to error | warning. Fixes info but keeps the word RFC 0109 removed from the result. Rejected.
• Store deal_flags verbatim in a new member and drop financial_validity[]. Cleaner mapping, but a larger change to a section whose other members are kept. Not proposed.

Unresolved questions

• thresholds_used lists no debt-yield or LTC limits (debt_yield_warning_below, ltc_warning_above, ltc_error_above). Adding them is a natural follow-up, but it is not part of the ruling.

Decisions (accepted 2026-10-21)

#	Question	Proposal	Why
D1	Member name and values	band: "error" | "warning", replacing severity	The ruling; matches DealFlag.band (RFC 0109 D2)
D2	metric vocabulary	Ruled: add ltc	RFC 0107 gave LTC a band
D3	Corpus entries with info	Ruled: removed; they cross no band	Not deal flags
D4	Retired severity	Not refused	As RFC 0108 D5
D5	Versions	None allocated; prelaunch 4.x	RFC 0091 D6

Prior art

• RFC 0109 (DealFlag.band) and RFC 0108 (the section speaks the result's words).