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diff --git a/‎content/docs/ui/translations.mdx‎
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diff --git a/‎packages/cli/src/commands/i18n/check.ts‎
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diff --git a/‎packages/cli/src/utils/i18n-coverage.ts‎
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@@ -0,0 +1,63 @@
+---
+"@objectstack/cli": minor
+---
+
+fix(cli): `os i18n check` counts the coverage an app actually owns, so `--strict` / `--threshold` can gate an app package (#16681)
+
+## What was wrong
+
+`collectExpectedEntries` walks the Studio metadata-form registries
+unconditionally — identically for every config, an empty one included — so
+every stack's expected set carries ~773 `metadataForms.*` keys that
+`@objectstack/platform-objects` translates and the runtime already serves.
+
+Two of the three commands that see that family already knew it is not the
+author's. `os lint` hides it and says so ("platform built-ins: 773 i18n
+issue(s) hidden — rerun with `--include-platform`"); `os i18n extract` has
+`--no-metadata-forms`. `os i18n check` is the one command that publishes a
+**percentage**, and it carried the baseline in its denominator:
+
+```
+Coverage by locale
+  en       ████████████████████████ 100.0%  (1265/1265, missing 0)
+  zh-CN    █████████░░░░░░░░░░░░░░░  38.9%  (492/1265, missing 773)
+```
+
+That is an application with every key it owns translated. `--strict` and
+`--threshold` — the two flags whose entire purpose is CI gating — therefore
+could not gate an app package at all, and the only way to move the number was
+to ship a copy of the platform's bundle, which would *override* the platform's
+own and go stale at the next upgrade. The workaround was worse than the defect.
+
+## What it does now
+
+**Ownership is observed, not assumed.** The baseline counts toward coverage
+when the stack under examination ships those translations itself, and does not
+when it does not — read from the config's own `translations` bundles, requiring
+a non-empty string leaf so an `--fill=empty` scaffold is not mistaken for a
+claim of ownership. An app gets a number about its own surface with no flag;
+`platform-objects`, which does ship the family, stays gated on it with no flag
+either. An unconditional exclusion would have turned the app side green by
+deleting the platform's own gate, and is what the negative-control tests forbid.
+
+**The flag is `os lint`'s, spelling and all.** `--include-platform` forces the
+baseline in; `--no-include-platform` forces it out, for a package that ships a
+partial baseline and does not intend to own the rest. Absent, the decision is
+the observed one — three states, not two.
+
+**Both output faces carry the decision.** `--json` gains
+`platformMetadataForms: { mode, excludedKeys }`, and the console prints
+`platform built-ins: N key(s) not counted — rerun with --include-platform to
+gate them here` under the coverage table, rendered from those same two numbers.
+
+`os lint` is unchanged. The shared `computeI18nCoverage` seam still counts the
+baseline by default, because lint folds it away one seam later and counts what
+it folded for its own hint line.
+
+## Compatibility
+
+Additive on the command surface; an invocation that was refused is now
+accepted, and no flag is removed or renamed. The behaviour that changes is the
+**default coverage number for a stack that ships no `metadataForms` bundle** —
+it stops reporting a debt that stack must not pay. A run that wants the old
+numbers back asks for them with `--include-platform`, on the same argv.
@@ -244,6 +244,23 @@ A missing string in the **default** locale is an error; missing strings in
 other locales are warnings until you set `--strict` / `--threshold`. The Todo
 example ships a completeness test alongside its bundles — worth copying.
 
+### What counts as *your* coverage
+
+The Studio's own metadata forms (`metadataForms.*` — several hundred keys
+across every metadata type) are translated by `@objectstack/platform-objects`
+and served from there, so they are **not** in your coverage number: an app that
+translated everything it declares reads 100%, not 39%. ⛔ Do not "fix" a low
+number by shipping your own `metadataForms` bundle — yours would override the
+platform's and go stale at the next upgrade.
+
+The rule is **ownership**, read from your own bundles rather than assumed: ship
+translations for that family and you are asked to complete them, which is how
+the platform packages stay gated on the strings they do own. Pass
+`--include-platform` to audit the baseline anyway (`os lint`'s flag, same
+meaning), or `--no-include-platform` to keep it out even though you ship part
+of it. The command prints how many keys it left out, and `--json` carries the
+same two numbers as `platformMetadataForms`.
+
 ### Which locales get checked
 
 Your project decides, and the tooling never assumes. `os lint`, `os i18n check`
 
@@ -1,5 +1,44 @@
 // Copyright (c) 2025 ObjectStack. Licensed under the Apache-2.0 license.
 
+/**
+ * `os i18n check` — the coverage gate.
+ *
+ * ## The platform `metadataForms.*` baseline, across all three commands
+ *
+ * `collectExpectedEntries` walks the Studio metadata-form registries
+ * unconditionally, identically for every config — ~773 keys that
+ * `@objectstack/platform-objects` translates and the runtime serves. Three
+ * commands see that family and each has to say something about it. They used
+ * to say three different things, and this one said nothing at all, which is
+ * how `--strict` / `--threshold` — the two flags whose entire purpose is CI
+ * gating — became unusable for an application package: every app read ~39%
+ * with its own surface fully translated, and the only way to "fix" the number
+ * was to ship a copy of the platform's bundle that would override it and go
+ * stale at the next upgrade.
+ *
+ *   command             what the baseline does to it     default        opt-in / out
+ *   ------------------  -------------------------------  -------------  ---------------------------
+ *   os lint             adds findings to the report      hidden         --include-platform
+ *   os i18n extract     adds a companion FILE / JSON      emitted        --no-metadata-forms
+ *                       member                                          (`metadataFormsCounts`
+ *                                                                       reports its size either way)
+ *   os i18n check       moves the coverage DENOMINATOR   auto: counted  --include-platform /
+ *                                                        only when      --no-include-platform
+ *                                                        this stack
+ *                                                        ships their
+ *                                                        translations
+ *
+ * ⚠️ The three differ because the OUTPUTS differ, and reading the table as
+ * three dialects of one setting is the mistake it exists to prevent: `lint`
+ * reports findings and can fold at the report seam; `extract` writes files and
+ * chooses a file set; only `check` publishes a **percentage**, so for it the
+ * question is which keys are in the denominator. That is also why this command
+ * is the one that can answer it without a flag — ownership of the baseline is
+ * observable from the config's own bundles ({@link stackAuthorsMetadataForms}),
+ * so an app gets its own number and `platform-objects`, which ships those
+ * translations, keeps being gated on them.
+ */
+
 import { Args, Command, Flags } from '@oclif/core';
 import chalk from 'chalk';
 import { normalizeStackInput } from '@objectstack/spec';
@@ -52,6 +91,7 @@ export default class I18nCheck extends Command {
     '$ os i18n check ./objectstack.config.ts',
     '$ os i18n check --locales=en,zh-CN,ja-JP',
     '$ os i18n check --strict --threshold=95',
+    '$ os i18n check --include-platform',
     '$ os i18n check --json',
   ];
 
@@ -78,6 +118,25 @@ export default class I18nCheck extends Command {
     'show-keys': Flags.boolean({
       description: 'List every missing key (otherwise the first 20 per locale are shown)',
     }),
+    // The same flag NAME and the same default as `os lint`, deliberately: this
+    // command was the odd one out of three, and a third vocabulary for one
+    // decision is what made an author go read the source to find out whether
+    // the platform bucket counts. `os i18n extract` spells its half
+    // `--no-metadata-forms`, which selects an emitted FILE SET rather than a
+    // gated population — see the table in the module note at the top of this
+    // file.
+    //
+    // `allowNo` gives the third state a percentage gate needs. Absent, the
+    // decision is `auto` — observed from the config, so neither an app nor the
+    // platform package has to discover a flag to get the right number.
+    // `--include-platform` forces the baseline in; `--no-include-platform`
+    // forces it out, for a package that ships a partial baseline and does not
+    // intend to own the rest of it.
+    'include-platform': Flags.boolean({
+      allowNo: true,
+      description:
+        'Count platform built-in metadata forms toward coverage (default: only when this stack ships their translations — the platform packages own them otherwise)',
+    }),
   };
 
   async run(): Promise<void> {
@@ -98,6 +157,14 @@ export default class I18nCheck extends Command {
         defaultLocale: flags['default-locale'],
         locales: flags.locales ? flags.locales.split(',').map((s) => s.trim()).filter(Boolean) : undefined,
         strict: flags.strict,
+        // Unset ⇒ `auto`. ⛔ Not `?? false`: an absent boolean and an explicit
+        // `--no-include-platform` are different requests here, and collapsing
+        // them would delete the observed-ownership default that makes this
+        // command usable without a flag on both sides.
+        platformMetadataForms:
+          flags['include-platform'] === undefined
+            ? 'auto'
+            : flags['include-platform'] ? 'include' : 'exclude',
       });
 
       const thresholdViolations = flags.threshold !== undefined
@@ -126,6 +193,17 @@ export default class I18nCheck extends Command {
           chalk.dim(`  (${stat.translated}/${stat.expected}, missing ${stat.missing})`),
         );
       }
+      // Printed under the table, where the denominator it explains is: every
+      // number above was computed without these keys. Same sentence shape as
+      // `os lint`'s, and rendered from the same two fields `--json` carries in
+      // `platformMetadataForms`, so the two faces cannot disagree.
+      if (report.platformMetadataForms.excludedKeys > 0) {
+        console.log(
+          chalk.dim(
+            `    platform built-ins: ${report.platformMetadataForms.excludedKeys} key(s) not counted — rerun with --include-platform to gate them here`,
+          ),
+        );
+      }
       console.log('');
 
       // ── Per-locale missing keys ──
 
@@ -99,8 +99,47 @@ export interface CoverageReport {
     errors: number;
     warnings: number;
   };
+  /**
+   * What this run did with the registry-driven `metadataForms.*` baseline, and
+   * how many keys that decision moved.
+   *
+   * Reported rather than left implicit because the decision moves the
+   * **denominator**: `stats[].expected` and `coveragePercent` mean different
+   * things under the two modes, and a consumer reading a percentage out of
+   * `os i18n check --json` has no other way to tell which one it is holding.
+   * The console hint line is rendered from these same two numbers, so the two
+   * faces of the command cannot disagree about it.
+   *
+   * `excludedKeys` is `0` under `'included'` — never absent, so a machine
+   * consumer keying off presence never has to distinguish "counted them" from
+   * "this version does not tell me".
+   */
+  platformMetadataForms: {
+    mode: PlatformMetadataFormsMode;
+    /** Authored platform keys dropped from the expected set (0 when included). */
+    excludedKeys: number;
+  };
 }
 
+/** The disposition a report actually reached — never `'auto'`, which is a request. */
+export type PlatformMetadataFormsMode = 'included' | 'excluded';
+
+/**
+ * What a caller asks for; {@link resolvePlatformMetadataForms} turns it into a
+ * {@link PlatformMetadataFormsMode}.
+ *
+ *  - `'include'` — count the baseline. The **default**, because `os lint` is
+ *    the other caller and it folds the baseline away at the REPORT seam
+ *    instead, off `CoverageIssue['source']`, so it needs the issues to exist
+ *    in order to count them for its `--include-platform` hint line. ⛔ Flipping
+ *    this default would zero that hint silently; `i18n-platform-bucket.test.ts`
+ *    pins the coupling.
+ *  - `'exclude'` — drop it.
+ *  - `'auto'` — drop it unless this stack authors it (see
+ *    {@link stackAuthorsMetadataForms}).
+ */
+export type PlatformMetadataFormsOption = 'include' | 'exclude' | 'auto';
+
 export interface CoverageOptions {
   /**
    * The locale that *must* be translated. Missing keys here surface as
@@ -119,6 +158,12 @@ export interface CoverageOptions {
    * errors. Useful for CI gates that demand full translation parity.
    */
   strict?: boolean;
+  /**
+   * How to treat the registry-driven `metadataForms.*` baseline. Defaults to
+   * `'include'` — see {@link PlatformMetadataFormsOption} for why that, and not
+   * `'auto'`, is the default at THIS seam.
+   */
+  platformMetadataForms?: PlatformMetadataFormsOption;
 }
 
 // ─── Bundle helpers ────────────────────────────────────────────────────
@@ -177,6 +222,74 @@ function flattenBundles(bundles: TranslationBundle[]): { merged: TranslationBund
   return { merged, locales: Array.from(localesSet).sort() };
 }
 
+// ─── Who owns the platform baseline ────────────────────────────────────
+
+/**
+ * Does this stack author the registry-driven `metadataForms.*` baseline
+ * itself?
+ *
+ * ## Why the question is asked of the CONFIG and not of a flag
+ *
+ * The `metadataForms.*` family is not walked out of the stack under
+ * examination at all: {@link collectExpectedEntries} builds it from
+ * `METADATA_FORM_REGISTRY` + `DEFAULT_METADATA_TYPE_REGISTRY`, identically for
+ * every config, empty ones included — ~773 Studio-form keys. For an
+ * application that is somebody else's surface: `@objectstack/platform-objects`
+ * ships those translations and the runtime serves them, so an app-shipped copy
+ * would *override* the platform's and go stale at the next upgrade. Counting
+ * them against an app's coverage percentage therefore reports a debt the app
+ * must not pay, which is what made `--strict` / `--threshold` unusable for an
+ * app package — the two flags whose entire purpose is CI gating.
+ *
+ * An unconditional exclusion is the wrong repair and is deliberately not what
+ * this is. It would turn the app side green by deleting the gate on the side
+ * that *does* own those strings: `platform-objects`' own extract config carries
+ * `metadataForms` in every locale bundle it declares, and its coverage number
+ * is a real number about real work. So ownership is **observed**, from the one
+ * place it is already written down — the bundles the stack itself attaches.
+ * Ship the baseline and you are asked to complete it; ship none of it and it
+ * is not yours.
+ *
+ * A non-empty **string leaf** is the test, not the mere presence of the group:
+ * an empty `metadataForms: {}`, or a scaffold of empty strings, is what `os
+ * i18n extract --fill=empty` leaves behind before anyone translates anything,
+ * and reading that as a claim of ownership would hand an app the 773-key debt
+ * on the strength of a placeholder. That is the same rule {@link lookupKey}
+ * applies on every other bundle read: an empty translation is not a
+ * translation.
+ */
+export function stackAuthorsMetadataForms(config: any): boolean {
+  const bundles: unknown[] = Array.isArray(config?.translations) ? config.translations : [];
+  const hasText = (node: unknown): boolean => {
+    if (typeof node === 'string') return node.length > 0;
+    if (!node || typeof node !== 'object' || Array.isArray(node)) return false;
+    return Object.values(node as Record<string, unknown>).some(hasText);
+  };
+  for (const bundle of bundles) {
+    if (!bundle || typeof bundle !== 'object') continue;
+    for (const data of Object.values(bundle as Record<string, unknown>)) {
+      if (!data || typeof data !== 'object') continue;
+      if (hasText((data as Record<string, unknown>).metadataForms)) return true;
+    }
+  }
+  return false;
+}
+
+/** Turn a caller's request into the disposition a report will record. */
+function resolvePlatformMetadataForms(
+  option: PlatformMetadataFormsOption | undefined,
+  config: any,
+): PlatformMetadataFormsMode {
+  switch (option ?? 'include') {
+    case 'exclude':
+      return 'excluded';
+    case 'auto':
+      return stackAuthorsMetadataForms(config) ? 'included' : 'excluded';
+    default:
+      return 'included';
+  }
+}
+
 // ─── Expected key extraction ───────────────────────────────────────────
 
 interface ExpectedKey {
@@ -501,12 +614,24 @@ export function computeI18nCoverage(config: any, opts: CoverageOptions = {}): Co
   // for two opposite facts.
   const authoredInBundle = (path: string[]): boolean =>
     Object.values(merged).some((data) => lookupKey(data, path) !== undefined);
-  const expected = collectExpectedKeys(config).filter(
+  const authored = collectExpectedKeys(config).filter(
     (key) =>
       key.inline !== undefined
       || inlineLocaleAny(key.inlineLocales) !== undefined
       || authoredInBundle(key.path),
   );
+
+  // The platform baseline is dropped from the POPULATION, not from the issue
+  // list, because this report's headline number is a percentage: an app that
+  // has translated every string it owns reads 38.9% while 773 of its 1265
+  // "expected" keys belong to `@objectstack/platform-objects`. `os lint` folds
+  // the same family away one seam later (`foldCoverageIssues`, keyed on
+  // `CoverageIssue['source']`) and can afford to, because it reports findings
+  // and never a denominator.
+  const platformMode = resolvePlatformMetadataForms(opts.platformMetadataForms, config);
+  const expected =
+    platformMode === 'included' ? authored : authored.filter((key) => key.source !== 'metadataForm');
+  const excludedPlatformKeys = authored.length - expected.length;
   const issues: CoverageIssue[] = [];
   const stats: CoverageStats[] = [];
 
@@ -570,5 +695,6 @@ export function computeI18nCoverage(config: any, opts: CoverageOptions = {}): Co
       errors,
       warnings,
     },
+    platformMetadataForms: { mode: platformMode, excludedKeys: excludedPlatformKeys },
   };
 }