@@ -230,7 +230,7 @@ const result = ApiMethod.parse(data);
 | **valueDomain** | `Enum<'iana_time_zone' \| 'iso_4217_currency' \| 'iso_3166_alpha2'>` | optional | Standard value domain the WRITTEN value must be a member of: `iana_time_zone` (an IANA/tzdb zone identifier such as `UTC`, `Asia/Kolkata`, `Europe/Kyiv` — membership is the `Intl.DateTimeFormat` probe, never the `Intl.supportedValuesOf` enumeration, which omits `UTC`), `iso_4217_currency` (an ISO 4217 alphabetic currency code, uppercase, e.g. `CHF`) or `iso_3166_alpha2` (an ISO 3166-1 alpha-2 country code, uppercase, e.g. `CH`). The same closed vocabulary and the same membership predicate as a settings specifier's `valueDomain`. Only authorable on `text` — the one type whose stored value is a single plain string naming the member. Checked on the WRITTEN value only (the `min`/`max`/`maxLength` transition-gate class): a stored value outside a domain declared later is never re-read and survives unrelated edits — only a write carrying a non-member is refused, with the field error code `value_domain`. Reach for it precisely where a pattern cannot help: `^[A-Z]{2}$` admits `ZZ`, and `Mars/Olympus` is a shape-valid zone that does not exist. |
 | **rows** | `integer` | optional | Height of the INLINE multiline editor, in text rows (positive integer — the HTML textarea `rows` attribute; fullscreen/dialog editor surfaces size themselves and ignore it). Only authorable on multiline editor types: textarea, markdown, html, richtext. Omit it for the widget default height. |
 | **precision** | `integer` | optional | Total digits (non-negative integer) |
-| **scale** | `integer` | optional | Decimal places (integer 0-100). OMITTED on a `percent` field ⇒ 0 decimal places, so a stored 0.25 reads `25%` on every face; omitted on any OTHER numeric type declares NO fixed width — the value keeps its natural precision, and a DECLARED `scale: 0` (a year, a fiscal period, an ordinal) stays distinguishable from having declared nothing, so nothing is defaulted there. Consumers resolve the effective width by calling `resolveFieldScale` from `@objectstack/spec/data`, the single source for an absent `scale`: a renderer that spells its own fallback is a width no other face can see, and that is how one stored 0.25 came to read `25%` on the read-only cell and `25.00%` in the edit widget. On a `percent` field this is the number of decimal places of the PERCENTAGE-POINT value as displayed and entered — `scale: 2` means 12.34% — and the STORED precision derives from the field's storage scale rather than being declared again: a fraction-stored percent (no `max`, or a `max` at or below 1) stores 12.34% as 0.1234 and is allowed `scale + 2` decimal places at the write seam, while a whole-percent field (`max` above 1) stores the displayed number itself and is allowed exactly `scale`. Every other numeric type is allowed exactly `scale`. The upper bound is the platform's, not a policy: renderers turn `scale` into fraction digits through `toFixed` and `Intl.NumberFormat`'s `maximumFractionDigits`, both of which throw a RangeError above 100 — so a larger declaration is unrenderable by any conforming consumer. |
+| **scale** | `integer` | optional | Decimal places (integer 0-100). Applies to `number`, `percent`, `rating` and `slider` fields, where it is enforced on writes, and to a `formula` field, whose computed result is rounded to it. REFUSED on a `currency` field — delete it there: a currency amount's decimal places are its currency's, so the currency's ISO 4217 minor unit decides how the amount displays, and a currency write's decimal places stay unconstrained. OMITTED on a `percent` field ⇒ 0 decimal places, so a stored 0.25 reads `25%` on every face; omitted on any OTHER numeric type declares NO fixed width — the value keeps its natural precision, and a DECLARED `scale: 0` (a year, a fiscal period, an ordinal) stays distinguishable from having declared nothing, so nothing is defaulted there. Consumers resolve the effective width by calling `resolveFieldScale` from `@objectstack/spec/data`, the single source for an absent `scale`: a renderer that spells its own fallback is a width no other face can see, and that is how one stored 0.25 came to read `25%` on the read-only cell and `25.00%` in the edit widget. On a `percent` field this is the number of decimal places of the PERCENTAGE-POINT value as displayed and entered — `scale: 2` means 12.34% — and the STORED precision derives from the field's storage scale rather than being declared again: a fraction-stored percent (no `max`, or a `max` at or below 1) stores 12.34% as 0.1234 and is allowed `scale + 2` decimal places at the write seam, while a whole-percent field (`max` above 1) stores the displayed number itself and is allowed exactly `scale`. `number`, `rating` and `slider` are allowed exactly `scale`. The upper bound is the platform's, not a policy: renderers turn `scale` into fraction digits through `toFixed` and `Intl.NumberFormat`'s `maximumFractionDigits`, both of which throw a RangeError above 100 — so a larger declaration is unrenderable by any conforming consumer. |
 | **min** | `number` | optional | Minimum value. Checked on the WRITTEN value only — the same transition-gate class as `requiredWhen`: an UPDATE validates just the fields the payload carries, so a stored value below a bound declared later is never re-read and survives unrelated edits; only a write that carries an out-of-bound value is refused, and a repairing write is accepted. For an invariant re-checked on every write, declare a `validations[]` `script` rule instead. |
 | **max** | `number` | optional | Maximum value. Checked on the WRITTEN value only — the same transition-gate class as `min`: a stored value above a bound declared later is never re-read and survives unrelated edits; only a write that carries an out-of-bound value is refused. For an invariant re-checked on every write, declare a `validations[]` `script` rule instead. |
 | **useGrouping** | `boolean` | optional | Digit-grouping presentation hint for `number` fields — maps to `Intl.NumberFormat`'s `useGrouping`. Absent = renderer decides (interim heuristic today, locale default eventually); `false` = author opts out of grouping (e.g. a year or other ordinal/identifier integer); `true` = author pins grouping on. |
@@ -562,7 +562,7 @@ const result = ApiMethod.parse(data);
 | **valueDomain** | `Enum<'iana_time_zone' \| 'iso_4217_currency' \| 'iso_3166_alpha2'>` | optional | Standard value domain the WRITTEN value must be a member of: `iana_time_zone` (an IANA/tzdb zone identifier such as `UTC`, `Asia/Kolkata`, `Europe/Kyiv` — membership is the `Intl.DateTimeFormat` probe, never the `Intl.supportedValuesOf` enumeration, which omits `UTC`), `iso_4217_currency` (an ISO 4217 alphabetic currency code, uppercase, e.g. `CHF`) or `iso_3166_alpha2` (an ISO 3166-1 alpha-2 country code, uppercase, e.g. `CH`). The same closed vocabulary and the same membership predicate as a settings specifier's `valueDomain`. Only authorable on `text` — the one type whose stored value is a single plain string naming the member. Checked on the WRITTEN value only (the `min`/`max`/`maxLength` transition-gate class): a stored value outside a domain declared later is never re-read and survives unrelated edits — only a write carrying a non-member is refused, with the field error code `value_domain`. Reach for it precisely where a pattern cannot help: `^[A-Z]{2}$` admits `ZZ`, and `Mars/Olympus` is a shape-valid zone that does not exist. |
 | **rows** | `integer` | optional | Height of the INLINE multiline editor, in text rows (positive integer — the HTML textarea `rows` attribute; fullscreen/dialog editor surfaces size themselves and ignore it). Only authorable on multiline editor types: textarea, markdown, html, richtext. Omit it for the widget default height. |
 | **precision** | `integer` | optional | Total digits (non-negative integer) |
-| **scale** | `integer` | optional | Decimal places (integer 0-100). OMITTED on a `percent` field ⇒ 0 decimal places, so a stored 0.25 reads `25%` on every face; omitted on any OTHER numeric type declares NO fixed width — the value keeps its natural precision, and a DECLARED `scale: 0` (a year, a fiscal period, an ordinal) stays distinguishable from having declared nothing, so nothing is defaulted there. Consumers resolve the effective width by calling `resolveFieldScale` from `@objectstack/spec/data`, the single source for an absent `scale`: a renderer that spells its own fallback is a width no other face can see, and that is how one stored 0.25 came to read `25%` on the read-only cell and `25.00%` in the edit widget. On a `percent` field this is the number of decimal places of the PERCENTAGE-POINT value as displayed and entered — `scale: 2` means 12.34% — and the STORED precision derives from the field's storage scale rather than being declared again: a fraction-stored percent (no `max`, or a `max` at or below 1) stores 12.34% as 0.1234 and is allowed `scale + 2` decimal places at the write seam, while a whole-percent field (`max` above 1) stores the displayed number itself and is allowed exactly `scale`. Every other numeric type is allowed exactly `scale`. The upper bound is the platform's, not a policy: renderers turn `scale` into fraction digits through `toFixed` and `Intl.NumberFormat`'s `maximumFractionDigits`, both of which throw a RangeError above 100 — so a larger declaration is unrenderable by any conforming consumer. |
+| **scale** | `integer` | optional | Decimal places (integer 0-100). Applies to `number`, `percent`, `rating` and `slider` fields, where it is enforced on writes, and to a `formula` field, whose computed result is rounded to it. REFUSED on a `currency` field — delete it there: a currency amount's decimal places are its currency's, so the currency's ISO 4217 minor unit decides how the amount displays, and a currency write's decimal places stay unconstrained. OMITTED on a `percent` field ⇒ 0 decimal places, so a stored 0.25 reads `25%` on every face; omitted on any OTHER numeric type declares NO fixed width — the value keeps its natural precision, and a DECLARED `scale: 0` (a year, a fiscal period, an ordinal) stays distinguishable from having declared nothing, so nothing is defaulted there. Consumers resolve the effective width by calling `resolveFieldScale` from `@objectstack/spec/data`, the single source for an absent `scale`: a renderer that spells its own fallback is a width no other face can see, and that is how one stored 0.25 came to read `25%` on the read-only cell and `25.00%` in the edit widget. On a `percent` field this is the number of decimal places of the PERCENTAGE-POINT value as displayed and entered — `scale: 2` means 12.34% — and the STORED precision derives from the field's storage scale rather than being declared again: a fraction-stored percent (no `max`, or a `max` at or below 1) stores 12.34% as 0.1234 and is allowed `scale + 2` decimal places at the write seam, while a whole-percent field (`max` above 1) stores the displayed number itself and is allowed exactly `scale`. `number`, `rating` and `slider` are allowed exactly `scale`. The upper bound is the platform's, not a policy: renderers turn `scale` into fraction digits through `toFixed` and `Intl.NumberFormat`'s `maximumFractionDigits`, both of which throw a RangeError above 100 — so a larger declaration is unrenderable by any conforming consumer. |
 | **min** | `number` | optional | Minimum value. Checked on the WRITTEN value only — the same transition-gate class as `requiredWhen`: an UPDATE validates just the fields the payload carries, so a stored value below a bound declared later is never re-read and survives unrelated edits; only a write that carries an out-of-bound value is refused, and a repairing write is accepted. For an invariant re-checked on every write, declare a `validations[]` `script` rule instead. |
 | **max** | `number` | optional | Maximum value. Checked on the WRITTEN value only — the same transition-gate class as `min`: a stored value above a bound declared later is never re-read and survives unrelated edits; only a write that carries an out-of-bound value is refused. For an invariant re-checked on every write, declare a `validations[]` `script` rule instead. |
 | **useGrouping** | `boolean` | optional | Digit-grouping presentation hint for `number` fields — maps to `Intl.NumberFormat`'s `useGrouping`. Absent = renderer decides (interim heuristic today, locale default eventually); `false` = author opts out of grouping (e.g. a year or other ordinal/identifier integer); `true` = author pins grouping on. |