fix: sync assistant runtime preferences

apps/nextjs/src/app/[locale]/manage/assistant/_components/assistant-configuration.tsx

@@ -256,6 +256,7 @@ export const AssistantConfiguration = () => {
       await Promise.all([
         utils.assistant.getAdminConfiguration.invalidate(),
         utils.assistant.getAvailability.invalidate(),
+        utils.assistant.getRuntimeOptions.invalidate(),
       ]);
       showSuccessNotification({
         title: t("notification.saved.title"),

apps/nextjs/src/components/assistant/assistant-panel.module.css

@@ -988,6 +988,10 @@
   flex: 1 1 auto;
 }
 
+.modelButton :global(.mantine-Button-label) {
+  font-size: var(--mantine-font-size-xs);
+}
+
 .reasoningButton {
   min-width: 7.5rem;
   max-width: 10.5rem;

apps/nextjs/src/components/assistant/assistant-preferences.spec.ts

@@ -0,0 +1,54 @@
+import { describe, expect, test } from "vitest";
+
+import { resolveAssistantPreferenceModelId } from "./assistant-preferences";
+
+const models = [
+  { id: "provider/default", name: "Default", inputModalities: ["text"] },
+  { id: "provider/alternate", name: "Alternate", inputModalities: ["text"] },
+];
+
+describe("resolveAssistantPreferenceModelId", () => {
+  test("uses the server default when preferences first load", () => {
+    expect(
+      resolveAssistantPreferenceModelId({
+        currentModelId: null,
+        previousDefaultModelId: undefined,
+        defaultModelId: "provider/default",
+        models,
+      }),
+    ).toBe("provider/default");
+  });
+
+  test("adopts a changed server default even when the old model remains available", () => {
+    expect(
+      resolveAssistantPreferenceModelId({
+        currentModelId: "provider/default",
+        previousDefaultModelId: "provider/default",
+        defaultModelId: "provider/alternate",
+        models,
+      }),
+    ).toBe("provider/alternate");
+  });
+
+  test("preserves an available conversation selection while the default is unchanged", () => {
+    expect(
+      resolveAssistantPreferenceModelId({
+        currentModelId: "provider/alternate",
+        previousDefaultModelId: "provider/default",
+        defaultModelId: "provider/default",
+        models,
+      }),
+    ).toBe("provider/alternate");
+  });
+
+  test("falls back to the default when the selected model is no longer available", () => {
+    expect(
+      resolveAssistantPreferenceModelId({
+        currentModelId: "provider/removed",
+        previousDefaultModelId: "provider/default",
+        defaultModelId: "provider/default",
+        models,
+      }),
+    ).toBe("provider/default");
+  });
+});

apps/nextjs/src/components/assistant/assistant-preferences.ts

@@ -5,3 +5,19 @@ export type AssistantRuntimeModelOption = {
   name: string;
   inputModalities: string[];
 };
+
+export const resolveAssistantPreferenceModelId = ({
+  currentModelId,
+  previousDefaultModelId,
+  defaultModelId,
+  models,
+}: {
+  currentModelId: string | null;
+  previousDefaultModelId: string | null | undefined;
+  defaultModelId: string | null;
+  models: readonly AssistantRuntimeModelOption[];
+}) => {
+  if (previousDefaultModelId !== defaultModelId) return defaultModelId;
+  if (currentModelId && models.some((model) => model.id === currentModelId)) return currentModelId;
+  return defaultModelId;
+};

apps/nextjs/src/components/assistant/assistant-provider.tsx

@@ -30,6 +30,7 @@ import { AssistantAskUserTool, AssistantConfigureAppTool } from "./assistant-hum
 import { AssistantPanel } from "./assistant-panel";
 import { getPendingAssistantAction } from "./assistant-pending-action";
 import type { AssistantReasoningMode, AssistantRuntimeModelOption } from "./assistant-preferences";
+import { resolveAssistantPreferenceModelId } from "./assistant-preferences";
 import { AssistantRuntimeProviderWithTools } from "./assistant-runtime-provider";
 import { sendAssistantPrompt as sendPromptThroughComposer } from "./assistant-send";
 import { createAssistantPromptInteraction } from "./assistant-spotlight";
@@ -163,6 +164,7 @@ const AssistantPreferencesProvider = ({ children }: PropsWithChildren) => {
   });
   const [modelId, setModelIdState] = useState<string | null>(null);
   const [reasoning, setReasoningState] = useState<AssistantReasoningMode>("auto");
+  const previousDefaultModelIdRef = useRef<string | null | undefined>(undefined);
   const preferencesRef = useRef<{ modelId: string | null; reasoning: AssistantReasoningMode }>({
     modelId: null,
     reasoning: "auto",
@@ -190,10 +192,17 @@ const AssistantPreferencesProvider = ({ children }: PropsWithChildren) => {
 
   useEffect(() => {
     if (!data) return;
-    const currentModelId = preferencesRef.current.modelId;
-    if (currentModelId && data.models.some((model) => model.id === currentModelId)) return;
-    setModelId(data.defaultModelId);
-  }, [data, setModelId]);
+    const nextModelId = resolveAssistantPreferenceModelId({
+      currentModelId: preferencesRef.current.modelId,
+      previousDefaultModelId: previousDefaultModelIdRef.current,
+      defaultModelId: data.defaultModelId,
+      models: data.models,
+    });
+    previousDefaultModelIdRef.current = data.defaultModelId;
+    if (nextModelId === preferencesRef.current.modelId) return;
+    preferencesRef.current.modelId = nextModelId;
+    setModelIdState(nextModelId);
+  }, [data]);
 
   const value = useMemo(
     () => ({

packages/translation/src/lang/en.json

@@ -1554,12 +1554,12 @@
         "noModels": "No models available",
         "thinking": "Thinking mode",
         "reasoning": {
-          "auto": "Thinking: Auto",
-          "none": "Thinking: Off",
-          "minimal": "Thinking: Minimal",
-          "low": "Thinking: Low",
-          "medium": "Thinking: Medium",
-          "high": "Thinking: High"
+          "auto": "Auto",
+          "none": "Off",
+          "minimal": "Minimal",
+          "low": "Low",
+          "medium": "Medium",
+          "high": "High"
         }
       },
       "stop": "Stop response",