fix(ui): harden target update flows in profile editors

- send strict target-only payloads when cliproxy edit only changes target

- route profile target updates through shared api client error handling

- block concurrent save/target actions in header controls

ui/src/components/cliproxy/cliproxy-edit-dialog.tsx

@@ -14,7 +14,7 @@ import { Label } from '@/components/ui/label';
 import { Tabs, TabsList, TabsTrigger, TabsContent } from '@/components/ui/tabs';
 import { useUpdateVariant } from '@/hooks/use-cliproxy';
 import { CLIPROXY_PROVIDERS, getProviderDisplayName } from '@/lib/provider-config';
-import type { Variant } from '@/lib/api-client';
+import type { UpdateVariant, Variant } from '@/lib/api-client';
 
 const singleProviderSchema = z.object({
   provider: z.enum(CLIPROXY_PROVIDERS, { message: 'Provider is required' }),
@@ -59,6 +59,63 @@ const providerOptions = CLIPROXY_PROVIDERS.map((id) => ({
   label: getProviderDisplayName(id),
 }));
 
+const COMPOSITE_TIERS = ['opus', 'sonnet', 'haiku'] as const;
+
+function normalizeOptionalValue(value?: string): string | undefined {
+  const trimmed = value?.trim();
+  return trimmed ? trimmed : undefined;
+}
+
+function isSingleVariantOnlyTargetChange(variant: Variant, data: SingleProviderFormData): boolean {
+  const currentTarget = variant.target || 'claude';
+  const currentModel = normalizeOptionalValue(variant.model);
+  const currentAccount = normalizeOptionalValue(variant.account);
+  const nextModel = normalizeOptionalValue(data.model);
+  const nextAccount = normalizeOptionalValue(data.account);
+
+  return (
+    data.target !== currentTarget &&
+    data.provider === variant.provider &&
+    nextModel === currentModel &&
+    nextAccount === currentAccount
+  );
+}
+
+function normalizeCompositeTier(tier: { provider: string; model: string; account?: string }) {
+  return {
+    provider: tier.provider,
+    model: tier.model.trim(),
+    account: normalizeOptionalValue(tier.account),
+  };
+}
+
+function isCompositeVariantOnlyTargetChange(variant: Variant, data: CompositeFormData): boolean {
+  const currentTarget = variant.target || 'claude';
+  const existingTiers = variant.tiers;
+
+  if (!existingTiers || !variant.default_tier) {
+    return false;
+  }
+
+  if (data.target === currentTarget) {
+    return false;
+  }
+
+  if (data.default_tier !== variant.default_tier) {
+    return false;
+  }
+
+  return COMPOSITE_TIERS.every((tier) => {
+    const current = normalizeCompositeTier(existingTiers[tier]);
+    const next = normalizeCompositeTier(data.tiers[tier]);
+    return (
+      next.provider === current.provider &&
+      next.model === current.model &&
+      next.account === current.account
+    );
+  });
+}
+
 export function CliproxyEditDialog({ variant, open, onOpenChange }: CliproxyEditDialogProps) {
   const updateMutation = useUpdateVariant();
   const isComposite = variant?.type === 'composite';
@@ -102,10 +159,40 @@ export function CliproxyEditDialog({ variant, open, onOpenChange }: CliproxyEdit
 
   const onSubmitSingle = async (data: SingleProviderFormData) => {
     if (!variant) return;
-    // Filter out undefined values - backend interprets undefined as "no change"
-    const payload = Object.fromEntries(
-      Object.entries(data).filter(([, v]) => v !== undefined && v !== '')
-    ) as SingleProviderFormData;
+
+    let payload: UpdateVariant = {};
+
+    if (isSingleVariantOnlyTargetChange(variant, data)) {
+      payload = { target: data.target };
+    } else {
+      const currentTarget = variant.target || 'claude';
+      const currentModel = normalizeOptionalValue(variant.model);
+      const currentAccount = normalizeOptionalValue(variant.account);
+      const nextModel = normalizeOptionalValue(data.model);
+      const nextAccount = normalizeOptionalValue(data.account);
+
+      if (data.provider !== variant.provider) {
+        payload.provider = data.provider;
+      }
+
+      if (nextModel !== currentModel) {
+        payload.model = nextModel;
+      }
+
+      if (nextAccount !== currentAccount) {
+        payload.account = nextAccount;
+      }
+
+      if (data.target !== currentTarget) {
+        payload.target = data.target;
+      }
+    }
+
+    if (Object.keys(payload).length === 0) {
+      onOpenChange(false);
+      return;
+    }
+
     try {
       await updateMutation.mutateAsync({ name: variant.name, data: payload });
       onOpenChange(false);
@@ -116,14 +203,53 @@ export function CliproxyEditDialog({ variant, open, onOpenChange }: CliproxyEdit
 
   const onSubmitComposite = async (data: CompositeFormData) => {
     if (!variant) return;
+
+    let payload: UpdateVariant = {};
+
+    if (isCompositeVariantOnlyTargetChange(variant, data)) {
+      payload = { target: data.target };
+    } else {
+      const existingTiers = variant.tiers;
+      const normalizedTiers: NonNullable<UpdateVariant['tiers']> = {
+        opus: normalizeCompositeTier(data.tiers.opus),
+        sonnet: normalizeCompositeTier(data.tiers.sonnet),
+        haiku: normalizeCompositeTier(data.tiers.haiku),
+      };
+
+      const tiersChanged = !existingTiers
+        ? true
+        : COMPOSITE_TIERS.some((tier) => {
+            const current = normalizeCompositeTier(existingTiers[tier]);
+            const next = normalizedTiers[tier];
+            return (
+              next.provider !== current.provider ||
+              next.model !== current.model ||
+              next.account !== current.account
+            );
+          });
+
+      if (variant.default_tier !== data.default_tier) {
+        payload.default_tier = data.default_tier;
+      }
+
+      if ((variant.target || 'claude') !== data.target) {
+        payload.target = data.target;
+      }
+
+      if (tiersChanged) {
+        payload.tiers = normalizedTiers;
+      }
+    }
+
+    if (Object.keys(payload).length === 0) {
+      onOpenChange(false);
+      return;
+    }
+
     try {
       await updateMutation.mutateAsync({
         name: variant.name,
-        data: {
-          default_tier: data.default_tier,
-          target: data.target,
-          tiers: data.tiers,
-        },
+        data: payload,
       });
       onOpenChange(false);
     } catch (error) {

ui/src/components/profiles/editor/header-section.tsx

@@ -49,6 +49,9 @@ export function HeaderSection({
   onDelete,
   onSave,
 }: HeaderSectionProps) {
+  const isMutating = isSaving || isTargetSaving;
+  const disableHeaderActions = isLoading || isMutating;
+
   return (
     <div className="px-6 py-4 border-b bg-background flex items-center justify-between shrink-0">
       <div>
@@ -68,8 +71,15 @@ export function HeaderSection({
         )}
         <div className="mt-2 flex items-center gap-2">
           <span className="text-xs text-muted-foreground">Default target:</span>
-          <Select value={target} onValueChange={(value) => onTargetChange(value as CliTarget)}>
-            <SelectTrigger className="h-7 w-[170px] text-xs" disabled={isTargetSaving}>
+          <Select
+            value={target}
+            onValueChange={(value) => {
+              if (disableHeaderActions) return;
+              onTargetChange(value as CliTarget);
+            }}
+            disabled={disableHeaderActions}
+          >
+            <SelectTrigger className="h-7 w-[170px] text-xs" disabled={disableHeaderActions}>
               <SelectValue />
             </SelectTrigger>
             <SelectContent>
@@ -81,15 +91,15 @@ export function HeaderSection({
         </div>
       </div>
       <div className="flex items-center gap-2">
-        <Button variant="ghost" size="sm" onClick={onRefresh} disabled={isLoading}>
+        <Button variant="ghost" size="sm" onClick={onRefresh} disabled={disableHeaderActions}>
           <RefreshCw className={`w-4 h-4 ${isLoading ? 'animate-spin' : ''}`} />
         </Button>
         {onDelete && (
-          <Button variant="ghost" size="sm" onClick={onDelete}>
+          <Button variant="ghost" size="sm" onClick={onDelete} disabled={isMutating}>
             <Trash2 className="w-4 h-4 text-destructive" />
           </Button>
         )}
-        <Button size="sm" onClick={onSave} disabled={isSaving || !hasChanges || !isRawJsonValid}>
+        <Button size="sm" onClick={onSave} disabled={isMutating || !hasChanges || !isRawJsonValid}>
           {isSaving ? (
             <>
               <Loader2 className="w-4 h-4 mr-1 animate-spin" />

ui/src/components/profiles/editor/index.tsx

@@ -15,7 +15,7 @@ import { HeaderSection } from './header-section';
 import { FriendlyUISection } from './friendly-ui-section';
 import { RawEditorSection } from './raw-editor-section';
 import type { ProfileEditorProps, Settings, SettingsResponse } from './types';
-import type { CliTarget } from '@/lib/api-client';
+import { api, type CliTarget } from '@/lib/api-client';
 
 export function ProfileEditor({
   profileName,
@@ -151,39 +151,24 @@ export function ProfileEditor({
     },
   });
 
-  const targetMutation = useMutation({
+  const targetMutation = useMutation<CliTarget, Error, CliTarget>({
     mutationFn: async (target: CliTarget) => {
-      const response = await fetch(`/api/profiles/${profileName}`, {
-        method: 'PUT',
-        headers: { 'Content-Type': 'application/json' },
-        body: JSON.stringify({ target }),
-      });
-
-      if (!response.ok) {
-        let errorMessage = 'Failed to update target';
-        try {
-          const payload = (await response.json()) as { error?: string };
-          if (payload.error) {
-            errorMessage = payload.error;
-          }
-        } catch {
-          // Keep fallback error message.
-        }
-        throw new Error(errorMessage);
-      }
-
-      return response.json();
+      await api.profiles.update(profileName, { target });
+      return target;
     },
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: ['profiles'] });
       toast.success('Default target updated');
     },
-    onError: (error: Error) => {
-      toast.error(error.message);
+    onError: (error: Error, target: CliTarget) => {
+      const targetLabel = target === 'droid' ? 'Factory Droid' : 'Claude Code';
+      const suffix = error.message.trim() ? `: ${error.message}` : '';
+      toast.error(`Failed to update default target to ${targetLabel}${suffix}`);
     },
   });
 
   const resolvedTarget: CliTarget = profileTarget || 'claude';
+  const isHeaderMutationPending = saveMutation.isPending || targetMutation.isPending;
 
   const handleConflictResolve = async (overwrite: boolean) => {
     setConflictDialog(false);
@@ -209,12 +194,19 @@ export function ProfileEditor({
         hasChanges={computedHasChanges}
         isRawJsonValid={computedIsRawJsonValid}
         onTargetChange={(target) => {
+          if (isHeaderMutationPending) return;
           if (target === resolvedTarget) return;
           targetMutation.mutate(target);
         }}
-        onRefresh={() => refetch()}
+        onRefresh={() => {
+          if (isHeaderMutationPending) return;
+          refetch();
+        }}
         onDelete={onDelete}
-        onSave={() => saveMutation.mutate()}
+        onSave={() => {
+          if (isHeaderMutationPending) return;
+          saveMutation.mutate();
+        }}
       />
 
       {isLoading ? (