fix(mobile): hide default session titles, state failures once, and shorten model-chip copy

apps/mobile/src/components/agents/markdown-renderer.test.ts

@@ -3,7 +3,7 @@
 import Module from 'node:module';
 import { createElement, type ReactElement, type ReactNode } from 'react';
 import { act, TestRenderer } from '@/test/renderer';
-import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
 
 import { confirmAndOpenMarkdownLink } from './markdown-link-confirm';
 
@@ -920,3 +920,55 @@ describe('MarkdownRenderer nested table fallback', () => {
     });
   });
 });
+
+/**
+ * Proof for the explorer's `session-tools-ar` finding: in the Arabic interface
+ * the assistant body and its bullet list read as centre-aligned, with the
+ * marker detached at the right edge (`session-tools-ar.png`). React Native only
+ * centres a paragraph through `textAlign`, so the renderer's contract is that
+ * the RTL path names the base direction (`writingDirection: 'rtl'`, from
+ * `lib/rtl-text.ts`) and no paragraph or marker style carries a `textAlign` at
+ * all. The marker box is the library's own; the renderer never gives it one.
+ */
+describe('MarkdownRenderer RTL paragraph direction (explorer session-tools-ar)', () => {
+  afterEach(() => {
+    rnStub.I18nManager.isRTL = false;
+  });
+
+  function elementStyle(element: ReactElement): Record<string, unknown> {
+    return flattenStyle((element.props as { style?: unknown }).style);
+  }
+
+  it('names the paragraph base direction without centring it', async () => {
+    rnStub.I18nManager.isRTL = true;
+    const renderer = await createRenderer();
+    const heading = renderer.heading('Why fork PRs can fail', { fontSize: 20 }) as ReactElement;
+    const body = renderer.escape('Secrets are withheld.', { fontSize: 16 }) as ReactElement;
+    const link = renderer.link('catalog.json', 'https://example.com', {
+      fontSize: 16,
+    }) as ReactElement;
+    for (const element of [heading, body, link]) {
+      const style = elementStyle(element);
+      expect(style.writingDirection).toBe('rtl');
+      expect(style.textAlign).toBeUndefined();
+    }
+  });
+
+  it('leaves the LTR path without a writing direction or alignment', async () => {
+    const renderer = await createRenderer();
+    const body = renderer.escape('Secrets are withheld.', { fontSize: 16 }) as ReactElement;
+    const style = elementStyle(body);
+    expect(style.writingDirection).toBeUndefined();
+    expect(style.textAlign).toBeUndefined();
+  });
+
+  it('has no centring style on the paragraph or list marker box', async () => {
+    const { getMarkdownStyles } = await import('./markdown-palette');
+    const styles = getMarkdownStyles(palette);
+    for (const key of ['text', 'paragraph', 'list', 'li'] as const) {
+      const style = flattenStyle(styles[key]);
+      expect(style.textAlign).toBeUndefined();
+      expect(style.alignItems).toBeUndefined();
+    }
+  });
+});

apps/mobile/src/components/agents/message-failure-state.test.ts

@@ -55,24 +55,24 @@ describe('selectMessageFailure', () => {
   });
 
   describe('delivery', () => {
-    it('maps every reason to fixed copy and never emits raw error text', () => {
+    it('maps every delivery reason to fixed copy and never emits raw error text', () => {
       const cases = [
-        { reason: 'interrupted', detail: 'You stopped this message.' },
+        { reason: 'interrupted', title: 'Failed to deliver', detail: 'You stopped this message.' },
         {
           reason: 'exhausted',
+          title: 'Failed to deliver',
           detail: 'We could not deliver this message after several attempts.',
         },
-        { reason: 'execution', detail: 'The agent could not run this message.' },
       ] as const;
 
-      for (const { reason, detail } of cases) {
+      for (const { reason, title, detail } of cases) {
         const result = selectMessageFailure({
           info: userInfo(),
           deliveryState: { status: 'failed', error: 'RAW_TRANSPORT_TEXT', reason },
         });
         expect(result).not.toBeNull();
         expect(result?.kind).toBe('delivery');
-        expect(result?.title).toBe('Failed to deliver');
+        expect(result?.title).toBe(title);
         expect(result?.detail).toBe(detail);
         expect(result?.title).not.toContain('RAW_TRANSPORT_TEXT');
         expect(result?.detail).not.toContain('RAW_TRANSPORT_TEXT');
@@ -83,6 +83,20 @@ describe('selectMessageFailure', () => {
       }
     });
 
+    it('states an agent-execution failure once, in the assistant-failure copy', () => {
+      const result = selectMessageFailure({
+        info: userInfo(),
+        deliveryState: { status: 'failed', error: 'RAW_TRANSPORT_TEXT', reason: 'execution' },
+      });
+      expect(result).not.toBeNull();
+      expect(result?.kind).toBe('delivery');
+      expect(result?.title).toBe('Response failed');
+      expect(result?.detail).toBeNull();
+      expect(result?.copyDetail).toBe('RAW_TRANSPORT_TEXT');
+      expect(result?.canRetry).toBe(true);
+      expect(result?.canCopy).toBe(true);
+    });
+
     it('exposes no copy detail when the delivery failure carries no transport text', () => {
       const result = selectMessageFailure({
         info: userInfo(),

apps/mobile/src/components/agents/message-failure-state.ts

@@ -11,9 +11,24 @@ type DeliveryReason = Extract<MessageDeliveryState, { status: 'failed' }>['reaso
 const DELIVERY_DETAIL_KEY_BY_REASON = {
   interrupted: 'agentChat.messageFailure.deliveryInterrupted',
   exhausted: 'agentChat.messageFailure.deliveryExhausted',
+  // `execution` is the response failure, not a delivery one (the message
+  // reached the agent): the row shows the assistant-failure title instead, so
+  // this line is never rendered. It stays in the record to keep the reason
+  // coverage complete.
   execution: 'agentChat.messageFailure.deliveryExecution',
 } as const satisfies Record<DeliveryReason, string>;
 
+/**
+ * The one delivery reason that is an agent run failing, not the transport: the
+ * message was delivered and the agent could not run it. The row states it in
+ * the assistant-failure copy ("Response failed") with no second line — the
+ * session's own status line reports the same failure, so a delivery-flavoured
+ * title here plus the footer's line read as the failure stated three times
+ * (UX-DEFECT session-detail failed turn). Retry and Copy-to-composer keep
+ * working: the transport text stays reachable behind the copy action.
+ */
+const AGENT_EXECUTION_DELIVERY_REASON: DeliveryReason = 'execution';
+
 /**
  * Assistant error names that can never be retried. Pinned to the exact names
  * in `packages/app-shared/src/opencode.gen.ts`.
@@ -25,22 +40,22 @@ export const NON_RETRYABLE_ASSISTANT_ERRORS: readonly string[] = [
 ];
 
 /**
- * Fixed, safe copy for a known assistant error name. An unknown name has no
- * line of its own: the title already states that the response failed, so the
- * footer adds no detail rather than repeating the title in a sentence
- * (`messageFailure.assistantFailed` is the fixed footer's line, not the
- * message row's). Never surfaces `error.data` or provider message text.
+ * The catalog key for a known assistant error name's fixed, safe detail line.
+ * An unknown name has no line of its own: the title already states that the
+ * response failed, so the footer adds no detail rather than repeating the title
+ * in a sentence (`messageFailure.assistantFailed` is the fixed footer's line,
+ * not the message row's). Never surfaces `error.data` or provider message text.
  */
-function assistantDetail(errorName: string): string | null {
+function assistantDetailKey(errorName: string): string | null {
   switch (errorName) {
     case 'ProviderAuthError': {
-      return i18n.t('agentChat.messageFailure.assistantProviderRejected');
+      return 'agentChat.messageFailure.assistantProviderRejected';
     }
     case 'MessageAbortedError': {
-      return i18n.t('agentChat.messageFailure.assistantStopped');
+      return 'agentChat.messageFailure.assistantStopped';
     }
     case 'ContextOverflowError': {
-      return i18n.t('agentChat.messageFailure.assistantContextOverflow');
+      return 'agentChat.messageFailure.assistantContextOverflow';
     }
     default: {
       return null;
@@ -50,11 +65,26 @@ function assistantDetail(errorName: string): string | null {
 
 export type MessageFailure = {
   kind: 'delivery' | 'assistant';
+  /**
+   * The catalog key behind `title`. The duplicate check compares keys, not the
+   * resolved copy: `selectMessageFailure` runs inside a memo keyed on the
+   * message arrays, so an in-place language switch would otherwise leave a
+   * stale-language title that no longer matches the footer copy resolved at
+   * render time.
+   */
+  titleKey: string;
   title: string;
   /**
-   * The explanation line under the title, or `null` when the title alone says
-   * it (an assistant failure with no classified reason). The footer then shows
-   * one statement plus the action rather than the same sentence twice.
+   * The catalog key behind `detail`, or `null` when the title alone says it (an
+   * assistant failure with no classified reason, or an agent-execution delivery
+   * failure whose response-failure title is the whole statement). The footer
+   * then shows one statement plus the action rather than the same sentence
+   * twice.
+   */
+  detailKey: string | null;
+  /**
+   * `detailKey` resolved at selection time, for rendering. `null` exactly when
+   * `detailKey` is `null`.
    */
   detail: string | null;
   /**
@@ -75,10 +105,25 @@ export function selectMessageFailure(input: {
   const { deliveryState, info } = input;
 
   if (info.role === 'user' && deliveryState?.status === 'failed') {
+    if (deliveryState.reason === AGENT_EXECUTION_DELIVERY_REASON) {
+      return {
+        kind: 'delivery',
+        titleKey: 'agentChat.messageFailure.assistantTitle',
+        title: i18n.t('agentChat.messageFailure.assistantTitle'),
+        detailKey: null,
+        detail: null,
+        copyDetail: deliveryState.error,
+        canRetry: true,
+        canCopy: true,
+      };
+    }
+    const detailKey = DELIVERY_DETAIL_KEY_BY_REASON[deliveryState.reason];
     return {
       kind: 'delivery',
+      titleKey: 'agentChat.messageFailure.deliveryTitle',
       title: i18n.t('agentChat.messageFailure.deliveryTitle'),
-      detail: i18n.t(DELIVERY_DETAIL_KEY_BY_REASON[deliveryState.reason]),
+      detailKey,
+      detail: i18n.t(detailKey),
       copyDetail: deliveryState.error,
       canRetry: true,
       canCopy: true,
@@ -87,10 +132,13 @@ export function selectMessageFailure(input: {
 
   if (info.role === 'assistant' && info.error) {
     const errorName = info.error.name;
+    const detailKey = assistantDetailKey(errorName);
     return {
       kind: 'assistant',
+      titleKey: 'agentChat.messageFailure.assistantTitle',
       title: i18n.t('agentChat.messageFailure.assistantTitle'),
-      detail: assistantDetail(errorName),
+      detailKey,
+      detail: detailKey === null ? null : i18n.t(detailKey),
       copyDetail: '',
       canRetry: !NON_RETRYABLE_ASSISTANT_ERRORS.includes(errorName),
       canCopy: false,

apps/mobile/src/components/agents/model-selector-label.test.ts

@@ -0,0 +1,65 @@
+import { describe, expect, it } from 'vitest';
+
+import { resolveModelSelectorLabel } from './model-selector-label';
+
+const FALLBACK = 'Model';
+
+describe('resolveModelSelectorLabel', () => {
+  it('uses the matched catalog option name', () => {
+    expect(
+      resolveModelSelectorLabel({
+        selectedName: 'DeepSeek V4 Flash 0731',
+        value: 'deepseek/deepseek-v4-flash-0731',
+        providerAware: false,
+        fallbackLabel: FALLBACK,
+      })
+    ).toBe('DeepSeek V4 Flash 0731');
+  });
+
+  it('strips the vendor prefix from an unmatched stored model reference', () => {
+    // The chip used to print this raw string verbatim (explorer
+    // session-typed-kb-up): it repeated the vendor as
+    // `DeepSeek: DeepSeek V4 Flash 0731`.
+    expect(
+      resolveModelSelectorLabel({
+        selectedName: undefined,
+        value: 'DeepSeek: DeepSeek V4 Flash 0731',
+        providerAware: false,
+        fallbackLabel: FALLBACK,
+      })
+    ).toBe('DeepSeek V4 Flash 0731');
+  });
+
+  it('keeps an unmatched value that carries no vendor prefix', () => {
+    expect(
+      resolveModelSelectorLabel({
+        selectedName: undefined,
+        value: 'custom-model-id',
+        providerAware: false,
+        fallbackLabel: FALLBACK,
+      })
+    ).toBe('custom-model-id');
+  });
+
+  it('falls back to the generic label when the value is empty', () => {
+    expect(
+      resolveModelSelectorLabel({
+        selectedName: undefined,
+        value: '',
+        providerAware: false,
+        fallbackLabel: FALLBACK,
+      })
+    ).toBe(FALLBACK);
+  });
+
+  it('falls back to the generic label for a provider-aware catalog miss', () => {
+    expect(
+      resolveModelSelectorLabel({
+        selectedName: undefined,
+        value: 'DeepSeek: DeepSeek V4 Flash 0731',
+        providerAware: true,
+        fallbackLabel: FALLBACK,
+      })
+    ).toBe(FALLBACK);
+  });
+});

apps/mobile/src/components/agents/model-selector-label.ts

@@ -0,0 +1,39 @@
+import { formatShortModelDisplayName } from '@/lib/model-display-name';
+
+type ModelSelectorLabelInput = {
+  /** The catalog option's display name, when the value matches one. */
+  selectedName: string | undefined;
+  /** The session's stored model reference or id. */
+  value: string;
+  /**
+   * True when the options carry CLI-catalog refs. The chip then cannot know a
+   * human name for an unmatched value and falls back to the generic label.
+   */
+  providerAware: boolean;
+  /** `t('common.model')`: the label when nothing else can be resolved. */
+  fallbackLabel: string;
+};
+
+/**
+ * The label for the `ModelSelector` chip.
+ *
+ * A session can report a model the local catalog does not carry (a CLI build
+ * ahead of the app's list), and the stored reference then arrives as the full
+ * `<Vendor>: <Model>` display name. Printing it verbatim repeats the vendor in
+ * user-facing copy — the chip read `DeepSeek: DeepSeek V4 Flash 0731` (explorer
+ * session-typed-kb-up) — so the chip falls back to the same short name the
+ * model picker shows. Mirrors the web chat toolbar, which never renders the raw
+ * model reference.
+ */
+export function resolveModelSelectorLabel(input: ModelSelectorLabelInput): string {
+  if (input.selectedName !== undefined) {
+    return input.selectedName;
+  }
+  if (!input.providerAware && input.value !== '') {
+    const shortName = formatShortModelDisplayName(input.value);
+    if (shortName !== '') {
+      return shortName;
+    }
+  }
+  return input.fallbackLabel;
+}

apps/mobile/src/components/agents/model-selector.tsx

@@ -25,6 +25,7 @@ import { modelPickerSlot } from '@/lib/route-registry';
 import { cn } from '@/lib/utils';
 
 import { modelSelectorBadges } from './model-selector-badges';
+import { resolveModelSelectorLabel } from './model-selector-label';
 
 type ModelSelectorProps = {
   value: string;
@@ -151,10 +152,18 @@ export function ModelSelector({
   const providerAware = pickerOptions.some(
     option => option.modelRef !== undefined || !option.showGatewayMetadata
   );
-  const fallbackLabel = !providerAware && value ? value : t('common.model');
-  const label = selectedModel
-    ? autoModelLabel(selectedModel.displayId, selectedModel.name)
-    : fallbackLabel;
+  // A matched option can be one of Kilo's own Auto models, whose backend name no
+  // catalog translates, so resolve its label first and let the helper fall back
+  // to the short name (or the generic label) for a stored reference the catalog
+  // does not carry.
+  const label = resolveModelSelectorLabel({
+    selectedName: selectedModel
+      ? autoModelLabel(selectedModel.displayId, selectedModel.name)
+      : undefined,
+    value,
+    providerAware,
+    fallbackLabel: t('common.model'),
+  });
   const { byok, collectsData } = modelSelectorBadges(selectedModel);
   const hasVariants = selectedModel ? selectedModel.variants.length > 1 : false;
   const variantLabel = variant ? thinkingEffortLabel(variant) : '';

apps/mobile/src/components/agents/new-session-screen-body.tsx

@@ -68,6 +68,7 @@ import {
 } from '@/lib/run-on-destination';
 import { shouldShowRunOnSelector } from '@/lib/should-show-run-on-selector';
 import { peekSharePayload } from '@/lib/share-payload';
+import { sessionDisplayTitle } from '@/lib/session-display-title';
 import { useNewSessionShareRemote } from '@/lib/use-new-session-share-remote';
 import { useNewSessionRepos } from '@/lib/use-new-session-repos';
 import { useTRPC } from '@/lib/trpc';
@@ -720,7 +721,7 @@ export function NewSessionScreenBody() {
         <View className="px-4 pt-4">
           <Text className="text-sm text-muted-foreground">
             {t('agentChat.newSession.continueFrom', {
-              title: cloneSourceTitle || t('agentChat.session.title'),
+              title: sessionDisplayTitle(cloneSourceTitle) ?? t('agentChat.session.title'),
             })}
           </Text>
         </View>