diff --git a/messages/de.json b/messages/de.json
index d749c64b4..d60aaf06c 100644
--- a/messages/de.json
+++ b/messages/de.json
@@ -8497,23 +8497,23 @@
     },
     "mcp": {
       "label": "Externer Assistentenzugriff (MCP)",
-      "description": "Einem MCP-fähigen Assistenten Lesezugriff auf deine Gesundheitsdaten über ein begrenztes Token erlauben. Standardmäßig aus."
+      "description": "Lesezugriff für einen MCP-fähigen Assistenten, über ein begrenztes Token."
     },
     "environment": {
       "label": "Umwelt",
-      "description": "Tägliches Wetter und Tageslicht für deinen Ort einbeziehen, um Zusammenhänge mit Stimmung, Schlaf und Vitalwerten zu erkennen. Standardmäßig aus."
+      "description": "Tägliches Wetter und Tageslicht für deinen Ort, neben Stimmung, Schlaf und Vitalwerten."
     },
     "inboundDocuments": {
       "label": "Dokumente",
-      "description": "Bewahre jedes medizinische Schreiben, jeden Befund und Scan an einem verschlüsselten, durchsuchbaren Ort auf — verknüpft mit deinen Erkrankungen. Standardmäßig aus."
+      "description": "Arztbriefe, Befunde und Scans verschlüsselt und durchsuchbar an einem Ort."
     },
     "mentalHealth": {
       "label": "Seelisches Wohlbefinden",
-      "description": "Freiwillige PHQ-9- und GAD-7-Selbsttests ergänzend zum Stimmungstagebuch. Standardmäßig aus; Antworten sind verschlüsselt und bleiben aus dem KI-Coach heraus."
+      "description": "Vier freiwillige Selbsttests neben dem Stimmungstagebuch."
     },
     "nutrients": {
       "label": "Nährstoffzufuhr",
-      "description": "Speichert tägliche Mikronährstoff-Summen (Vitamine, Mineralstoffe, Wasser, Koffein) aus Apple Health. Standardmäßig aus."
+      "description": "Tägliche Mikronährstoff-Summen aus Apple Health."
     }
   },
   "illness": {
@@ -9010,7 +9010,8 @@
     },
     "openDetail": "Details anzeigen",
     "historyLoadError": "Dein Testverlauf konnte nicht geladen werden",
-    "historyLoadErrorHint": "Das heißt nicht, dass keine Ergebnisse vorliegen — die Liste konnte nicht abgerufen werden. Versuche es erneut."
+    "historyLoadErrorHint": "Das heißt nicht, dass keine Ergebnisse vorliegen — die Liste konnte nicht abgerufen werden. Versuche es erneut.",
+    "privacyNote": "Deine Antworten sind verschlüsselt gespeichert und erreichen den KI-Coach nicht."
   },
   "records": {
     "aiInclusion": {
diff --git a/messages/en.json b/messages/en.json
index 3ab28641f..bcf9dbf47 100644
--- a/messages/en.json
+++ b/messages/en.json
@@ -8497,23 +8497,23 @@
     },
     "mcp": {
       "label": "External assistant access (MCP)",
-      "description": "Let an MCP-capable assistant read your health data over a scoped token. Off by default."
+      "description": "Read access for an MCP-capable assistant, over a scoped token."
     },
     "environment": {
       "label": "Environment",
-      "description": "Pull in daily weather and daylight for your location to correlate with mood, sleep, and vitals. Off by default."
+      "description": "Daily weather and daylight for your location, beside mood, sleep, and vitals."
     },
     "inboundDocuments": {
       "label": "Documents",
-      "description": "Keep every medical letter, report, and scan in one encrypted, searchable place — linked to your conditions. Off by default."
+      "description": "Medical letters, reports, and scans in one encrypted, searchable place."
     },
     "mentalHealth": {
       "label": "Mental wellbeing",
-      "description": "Opt-in PHQ-9 and GAD-7 screeners beside mood tracking. Off by default; answers are encrypted and kept out of the AI Coach."
+      "description": "Four opt-in screeners beside mood tracking."
     },
     "nutrients": {
       "label": "Nutrient intake",
-      "description": "Store daily micronutrient totals (vitamins, minerals, water, caffeine) synced from Apple Health. Off by default."
+      "description": "Daily micronutrient totals synced from Apple Health."
     }
   },
   "illness": {
@@ -9010,7 +9010,8 @@
     },
     "openDetail": "Show details",
     "historyLoadError": "Your assessment history could not be loaded",
-    "historyLoadErrorHint": "This does not mean you have no results — the list could not be fetched. Try again."
+    "historyLoadErrorHint": "This does not mean you have no results — the list could not be fetched. Try again.",
+    "privacyNote": "Your answers are stored encrypted and never reach the AI Coach."
   },
   "records": {
     "aiInclusion": {
diff --git a/messages/es.json b/messages/es.json
index ff86aae20..54791c8d1 100644
--- a/messages/es.json
+++ b/messages/es.json
@@ -8497,23 +8497,23 @@
     },
     "mcp": {
       "label": "Acceso de asistente externo (MCP)",
-      "description": "Permite que un asistente compatible con MCP lea tus datos de salud mediante un token con alcance limitado. Desactivado de forma predeterminada."
+      "description": "Acceso de lectura para un asistente compatible con MCP, mediante un token limitado."
     },
     "environment": {
       "label": "Entorno",
-      "description": "Incorpora el tiempo y las horas de luz diarias de tu ubicación para correlacionarlos con el ánimo, el sueño y las constantes. Desactivado por defecto."
+      "description": "El tiempo y las horas de luz diarias de tu ubicación, junto al ánimo, el sueño y las constantes."
     },
     "inboundDocuments": {
       "label": "Documentos",
-      "description": "Guarda cada carta médica, informe y escaneo en un solo lugar cifrado y con búsqueda — vinculado a tus afecciones. Desactivado por defecto."
+      "description": "Cartas médicas, informes y escaneos en un lugar cifrado y con búsqueda."
     },
     "mentalHealth": {
       "label": "Bienestar mental",
-      "description": "Cuestionarios PHQ-9 y GAD-7 opcionales, junto al registro de ánimo. Desactivado por defecto; las respuestas se cifran y se mantienen fuera del Coach de IA."
+      "description": "Cuatro cuestionarios opcionales, junto al registro de ánimo."
     },
     "nutrients": {
       "label": "Ingesta de nutrientes",
-      "description": "Guarda los totales diarios de micronutrientes (vitaminas, minerales, agua, cafeína) sincronizados desde Apple Health. Desactivado por defecto."
+      "description": "Totales diarios de micronutrientes sincronizados desde Apple Health."
     }
   },
   "illness": {
@@ -9010,7 +9010,8 @@
     },
     "openDetail": "Ver detalles",
     "historyLoadError": "No se pudo cargar tu historial de evaluaciones",
-    "historyLoadErrorHint": "Esto no significa que no tengas resultados: no se pudo obtener la lista. Vuelve a intentarlo."
+    "historyLoadErrorHint": "Esto no significa que no tengas resultados: no se pudo obtener la lista. Vuelve a intentarlo.",
+    "privacyNote": "Tus respuestas se guardan cifradas y nunca llegan al Coach de IA."
   },
   "records": {
     "aiInclusion": {
diff --git a/messages/fr.json b/messages/fr.json
index 0731663e4..5bebe5ce5 100644
--- a/messages/fr.json
+++ b/messages/fr.json
@@ -8497,23 +8497,23 @@
     },
     "mcp": {
       "label": "Accès assistant externe (MCP)",
-      "description": "Autorise un assistant compatible MCP à lire vos données de santé via un jeton à portée limitée. Désactivé par défaut."
+      "description": "Accès en lecture pour un assistant compatible MCP, via un jeton limité."
     },
     "environment": {
       "label": "Environnement",
-      "description": "Intégrez la météo et la durée du jour quotidiennes de votre lieu pour les corréler à l'humeur, au sommeil et aux constantes. Désactivé par défaut."
+      "description": "Météo et durée du jour quotidiennes de votre lieu, à côté de l'humeur, du sommeil et des constantes."
     },
     "inboundDocuments": {
       "label": "Documents",
-      "description": "Conservez chaque courrier médical, compte rendu et scan dans un espace chiffré et consultable — lié à vos affections. Désactivé par défaut."
+      "description": "Courriers médicaux, comptes rendus et scans dans un espace chiffré et consultable."
     },
     "mentalHealth": {
       "label": "Bien-être mental",
-      "description": "Questionnaires PHQ-9 et GAD-7 facultatifs, en complément du suivi de l'humeur. Désactivé par défaut ; les réponses sont chiffrées et tenues à l'écart du Coach IA."
+      "description": "Quatre questionnaires facultatifs, à côté du suivi de l'humeur."
     },
     "nutrients": {
       "label": "Apports en nutriments",
-      "description": "Enregistre les totaux quotidiens de micronutriments (vitamines, minéraux, eau, caféine) synchronisés depuis Apple Health. Désactivé par défaut."
+      "description": "Totaux quotidiens de micronutriments synchronisés depuis Apple Health."
     }
   },
   "illness": {
@@ -9010,7 +9010,8 @@
     },
     "openDetail": "Voir les détails",
     "historyLoadError": "Ton historique d'évaluations n'a pas pu être chargé",
-    "historyLoadErrorHint": "Cela ne veut pas dire que tu n'as aucun résultat : la liste n'a pas pu être récupérée. Réessaie."
+    "historyLoadErrorHint": "Cela ne veut pas dire que tu n'as aucun résultat : la liste n'a pas pu être récupérée. Réessaie.",
+    "privacyNote": "Vos réponses sont stockées chiffrées et n'atteignent jamais le Coach IA."
   },
   "records": {
     "aiInclusion": {
diff --git a/messages/it.json b/messages/it.json
index e4528699f..a453e7c92 100644
--- a/messages/it.json
+++ b/messages/it.json
@@ -8497,23 +8497,23 @@
     },
     "mcp": {
       "label": "Accesso assistente esterno (MCP)",
-      "description": "Consente a un assistente compatibile con MCP di leggere i tuoi dati sanitari tramite un token con ambito limitato. Disattivato per impostazione predefinita."
+      "description": "Accesso in lettura per un assistente compatibile con MCP, tramite un token limitato."
     },
     "environment": {
       "label": "Ambiente",
-      "description": "Integra il meteo e le ore di luce giornaliere della tua posizione per correlarli con umore, sonno e parametri vitali. Disattivato di default."
+      "description": "Meteo e ore di luce giornaliere della tua posizione, accanto a umore, sonno e parametri vitali."
     },
     "inboundDocuments": {
       "label": "Documenti",
-      "description": "Conserva ogni lettera medica, referto e scansione in un unico archivio cifrato e ricercabile — collegato alle tue patologie. Disattivato di default."
+      "description": "Lettere mediche, referti e scansioni in un archivio cifrato e ricercabile."
     },
     "mentalHealth": {
       "label": "Benessere mentale",
-      "description": "Questionari PHQ-9 e GAD-7 facoltativi, accanto al diario dell'umore. Disattivato per impostazione predefinita; le risposte sono cifrate e tenute fuori dal Coach IA."
+      "description": "Quattro questionari facoltativi, accanto al diario dell'umore."
     },
     "nutrients": {
       "label": "Assunzione di nutrienti",
-      "description": "Salva i totali giornalieri di micronutrienti (vitamine, minerali, acqua, caffeina) sincronizzati da Apple Health. Disattivato per impostazione predefinita."
+      "description": "Totali giornalieri di micronutrienti sincronizzati da Apple Health."
     }
   },
   "illness": {
@@ -9010,7 +9010,8 @@
     },
     "openDetail": "Mostra dettagli",
     "historyLoadError": "Non è stato possibile caricare la cronologia dei test",
-    "historyLoadErrorHint": "Questo non significa che non ci siano risultati: non è stato possibile recuperare l'elenco. Riprova."
+    "historyLoadErrorHint": "Questo non significa che non ci siano risultati: non è stato possibile recuperare l'elenco. Riprova.",
+    "privacyNote": "Le tue risposte sono salvate cifrate e non raggiungono mai il Coach IA."
   },
   "records": {
     "aiInclusion": {
diff --git a/messages/pl.json b/messages/pl.json
index 1e4bc806c..5027504c1 100644
--- a/messages/pl.json
+++ b/messages/pl.json
@@ -8497,23 +8497,23 @@
     },
     "mcp": {
       "label": "Dostęp asystenta zewnętrznego (MCP)",
-      "description": "Pozwól asystentowi obsługującemu MCP czytać Twoje dane zdrowotne za pomocą tokena o ograniczonym zakresie. Domyślnie wyłączone."
+      "description": "Dostęp do odczytu dla asystenta obsługującego MCP, przez token o ograniczonym zakresie."
     },
     "environment": {
       "label": "Środowisko",
-      "description": "Pobieraj dzienną pogodę i długość dnia dla swojej lokalizacji, aby powiązać je z nastrojem, snem i parametrami życiowymi. Domyślnie wyłączone."
+      "description": "Dzienna pogoda i długość dnia dla Twojej lokalizacji, obok nastroju, snu i parametrów życiowych."
     },
     "inboundDocuments": {
       "label": "Dokumenty",
-      "description": "Przechowuj każde pismo lekarskie, wynik i skan w jednym zaszyfrowanym, przeszukiwalnym miejscu — powiązane z Twoimi schorzeniami. Domyślnie wyłączone."
+      "description": "Pisma lekarskie, wyniki i skany w jednym zaszyfrowanym, przeszukiwalnym miejscu."
     },
     "mentalHealth": {
       "label": "Dobrostan psychiczny",
-      "description": "Dobrowolne testy PHQ-9 i GAD-7 obok dziennika nastroju. Domyślnie wyłączone; odpowiedzi są szyfrowane i pozostają poza Coachem AI."
+      "description": "Cztery dobrowolne testy obok dziennika nastroju."
     },
     "nutrients": {
       "label": "Spożycie składników odżywczych",
-      "description": "Zapisuje dzienne sumy mikroskładników (witaminy, minerały, woda, kofeina) synchronizowane z Apple Health. Domyślnie wyłączone."
+      "description": "Dzienne sumy mikroskładników synchronizowane z Apple Health."
     }
   },
   "illness": {
@@ -9010,7 +9010,8 @@
     },
     "openDetail": "Pokaż szczegóły",
     "historyLoadError": "Nie udało się wczytać historii testów",
-    "historyLoadErrorHint": "To nie znaczy, że nie masz wyników — nie udało się pobrać listy. Spróbuj ponownie."
+    "historyLoadErrorHint": "To nie znaczy, że nie masz wyników — nie udało się pobrać listy. Spróbuj ponownie.",
+    "privacyNote": "Twoje odpowiedzi są przechowywane w postaci zaszyfrowanej i nigdy nie trafiają do Coacha AI."
   },
   "records": {
     "aiInclusion": {
diff --git a/src/components/mental-health/mental-wellbeing.tsx b/src/components/mental-health/mental-wellbeing.tsx
index b33f3902f..abbe508d0 100644
--- a/src/components/mental-health/mental-wellbeing.tsx
+++ b/src/components/mental-health/mental-wellbeing.tsx
@@ -142,6 +142,17 @@ export function MentalWellbeing() {
             description={t("mentalHealth.pageDescription")}
           />
 
+          {/* What happens to the answers. The Modules hub used to carry this
+              as the second sentence of the module's one-line description,
+              which was the only place in the app that said it — so it moved
+              to the screen where somebody is about to answer. */}
+          <p
+            data-slot="mental-health-privacy-note"
+            className="text-muted-foreground -mt-3 text-xs"
+          >
+            {t("mentalHealth.privacyNote")}
+          </p>
+
           <section aria-label={t("mentalHealth.choosePrompt")}>
             <h2 className="sr-only">{t("mentalHealth.choosePrompt")}</h2>
             {historyError ? (
diff --git a/src/components/settings/__tests__/module-description-length.test.ts b/src/components/settings/__tests__/module-description-length.test.ts
new file mode 100644
index 000000000..3634f2b3b
--- /dev/null
+++ b/src/components/settings/__tests__/module-description-length.test.ts
@@ -0,0 +1,77 @@
+import { describe, it, expect } from "vitest";
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+
+import { MODULE_KEYS } from "@/lib/modules/registry";
+import { locales } from "@/lib/i18n/config";
+
+/**
+ * A module row in the "What you track" hub gets ONE sentence, same as a card
+ * header's description slot (design standards §3).
+ *
+ * Five of the eighteen rows had grown a second sentence — always the same
+ * one, "Off by default", and in one case a third clause after it. The
+ * neighbours sat at 30-75 characters and those five at 120-165, so the hub
+ * read as two different lists stacked on each other. The switch beside the
+ * row already says whether the module is on, so the sentence was restating
+ * what the control shows.
+ *
+ * The single-sentence half of the rule is checked in every locale: it is a
+ * structural claim, not a length one, and a translation that re-adds the
+ * clause is the same defect. The character cap is checked in EN and DE, the
+ * two the maintainer reads, matching `card-description-length.test.ts`.
+ */
+
+const ROOT = process.cwd();
+const MAX_CHARS = 120;
+
+function bundle(locale: string): Record<string, { description?: string }> {
+  const raw = readFileSync(join(ROOT, "messages", `${locale}.json`), "utf8");
+  return JSON.parse(raw).modules;
+}
+
+describe("module hub descriptions", () => {
+  it("names a description for every module in every locale", () => {
+    // Positive control: without it, a renamed `modules` namespace would make
+    // the two checks below iterate an empty set and report green.
+    for (const locale of locales) {
+      const modules = bundle(locale);
+      const missing = MODULE_KEYS.filter(
+        (key) => !modules[key]?.description?.trim(),
+      );
+      expect(missing, `${locale} is missing descriptions`).toEqual([]);
+    }
+  });
+
+  it("holds each one to a single sentence, in every locale", () => {
+    const offenders: string[] = [];
+    for (const locale of locales) {
+      const modules = bundle(locale);
+      for (const key of MODULE_KEYS) {
+        const text = modules[key].description!;
+        // Drop the closing terminator, then any sentence break left inside
+        // is a second sentence. A semicolon splice counts — it is how the
+        // longest of the five carried its third clause.
+        const body = text.replace(/[.!?…]\s*$/, "");
+        if (/[.!?;]\s/.test(body)) {
+          offenders.push(`${locale}/${key}: ${text}`);
+        }
+      }
+    }
+    expect(offenders).toEqual([]);
+  });
+
+  it("holds each one under the character guideline in EN and DE", () => {
+    const offenders: string[] = [];
+    for (const locale of ["en", "de"] as const) {
+      const modules = bundle(locale);
+      for (const key of MODULE_KEYS) {
+        const text = modules[key].description!;
+        if (text.length > MAX_CHARS) {
+          offenders.push(`${locale}/${key}: ${text.length} chars`);
+        }
+      }
+    }
+    expect(offenders).toEqual([]);
+  });
+});