diff --git a/.project-docs/30-worklog/tasks/20260823-pi-chat-timeline-c8f31a62.md b/.project-docs/30-worklog/tasks/20260823-pi-chat-timeline-c8f31a62.md
index e09f148..253fb89 100644
--- a/.project-docs/30-worklog/tasks/20260823-pi-chat-timeline-c8f31a62.md
+++ b/.project-docs/30-worklog/tasks/20260823-pi-chat-timeline-c8f31a62.md
@@ -151,6 +151,14 @@
   behind a buffered continuous tail, Renderer requests one fresh target
   Snapshot; a repeated identical stale response becomes a retryable error
   instead of remaining in an infinite recovering state.
+- Closed the incremental planner review findings after `bec93d0`: attachment
+  editing is locked for the originating Conversation until upload and HTTP 202
+  acceptance settle, so removal or a next-message paste cannot mutate the
+  captured image set. Attachment preparation failures now remain local to the
+  Composer, restore the draft, permit direct retry without runtime recovery,
+  and retain already uploaded variants for reuse. Attachment route failures use
+  only registered `CODING_ATTACHMENT_INVALID`, `CODING_ATTACHMENT_NOT_FOUND`,
+  and `CODING_STORAGE_WRITE_FAILED` codes while preserving 413/404 status.
 - Synchronized `README.md` with the current Pi core Chat, first-Conversation,
   batch and attachment behavior. PI-130 feature controls and PI-140 legacy
   removal remain outside this task.
@@ -161,6 +169,10 @@
   **Standards Needs Fix / Spec Needs Fix**. PI-120 remained the unique Ready
   Frontier; the findings above were treated as blocking rather than advancing
   PI-130.
+- The correction candidate `bec93d0` received incremental planner review result
+  **Standards PASS / Spec Needs Fix**. Its three remaining attachment-state and
+  typed-error findings were implemented and kept PI-130 locked pending another
+  planner review.
 - Post-review focused suites passed: attachment Host routes, stale recovery,
   shared ProjectService/Registry mutation queue, slow Agent switch, cross-
   Conversation submission isolation, attachment count/concurrency and pressure
@@ -171,7 +183,11 @@
   20 React commits, 131,148 wire bytes, and measured Main-to-React p95
   `35.995 ms` against the `<=50 ms` budget. It includes mixed message blocks,
   4 KiB tool output and more than 100 KiB of cumulative thinking output.
-- `pnpm test`: passed, 218 files / 2316 passed / 2 skipped.
+- Latest attachment-state focused run passed: 3 files / 39 tests, including
+  delayed upload/removal, delayed HTTP 202/next-image isolation, local
+  preparation failure/direct retry, uploaded-variant reuse, and registered
+  Host error codes.
+- `pnpm test`: passed, 218 files / 2321 passed / 2 skipped.
 - `pnpm run typecheck`: passed.
 - `pnpm run lint:check`: passed with 0 errors and six unchanged warnings in
   `ExecutionGraphCard`, `Home`, and `Makelore`.
diff --git a/electron/api/routes/coding-attachments.ts b/electron/api/routes/coding-attachments.ts
index 4dee2a3..f9de310 100644
--- a/electron/api/routes/coding-attachments.ts
+++ b/electron/api/routes/coding-attachments.ts
@@ -66,28 +66,32 @@ async function readBoundedBody(req: IncomingMessage): Promise<Uint8Array> {
   return Buffer.concat(chunks);
 }
 
-function sendAttachmentError(res: ServerResponse, error: unknown): void {
-  const status = typeof (error as { status?: unknown })?.status === 'number'
+function sendAttachmentError(
+  res: ServerResponse,
+  error: unknown,
+  operation: 'upload' | 'content',
+): void {
+  const explicitStatus = typeof (error as { status?: unknown })?.status === 'number'
     ? (error as { status: number }).status
-    : (error as NodeJS.ErrnoException)?.code === 'ENOENT'
-      ? 404
-      : 500;
+    : null;
+  const status = explicitStatus
+    ?? (operation === 'content' || (error as NodeJS.ErrnoException)?.code === 'ENOENT' ? 404 : 500);
   const message = status === 413
     ? '图片不能超过 16 MB。'
     : status === 404
       ? '图片附件不存在。'
       : status === 400
         ? '图片附件无效。'
-        : '图片附件暂时无法读取。';
+        : operation === 'upload'
+          ? '本地数据写入失败，请检查存储后重试。'
+          : '图片附件暂时无法读取。';
   sendJson(res, status, {
     success: false,
-    code: status === 413
-      ? 'CODING_ATTACHMENT_TOO_LARGE'
+    code: status === 400 || status === 413
+      ? 'CODING_ATTACHMENT_INVALID'
       : status === 404
         ? 'CODING_ATTACHMENT_NOT_FOUND'
-        : status === 400
-          ? 'CODING_ATTACHMENT_INVALID'
-          : 'CODING_ATTACHMENT_STORAGE_FAILED',
+        : 'CODING_STORAGE_WRITE_FAILED',
     error: message,
   });
 }
@@ -147,7 +151,7 @@ export async function handleCodingAttachmentRoutes(
     res.end(record.data);
     return true;
   } catch (error) {
-    sendAttachmentError(res, error);
+    sendAttachmentError(res, error, upload ? 'upload' : 'content');
     return true;
   }
 }
diff --git a/src/pages/Chat/CodingChatPanel.tsx b/src/pages/Chat/CodingChatPanel.tsx
index 749688c..318ac28 100644
--- a/src/pages/Chat/CodingChatPanel.tsx
+++ b/src/pages/Chat/CodingChatPanel.tsx
@@ -301,7 +301,8 @@ export function CodingChatPanel({
   ]);
 
   const handleAddFiles = useCallback((files: File[]) => {
-    if (!draftKey) return;
+    if (!draftKey
+      || (targetConversationId && submissionFlightsRef.current.has(targetConversationId))) return;
     const accepted: LocalComposerAttachment[] = [];
     const remaining = Math.max(0, CODING_ATTACHMENT_MAX_COUNT - localAttachments.length);
     let validationError = files.length > remaining
@@ -335,10 +336,11 @@ export function CodingChatPanel({
       ...current,
       [draftKey]: [...(current[draftKey] ?? []), ...accepted],
     }));
-  }, [draftKey, localAttachments.length]);
+  }, [draftKey, localAttachments.length, targetConversationId]);
 
   const handleRemoveAttachment = useCallback((id: string) => {
-    if (!draftKey) return;
+    if (!draftKey
+      || (targetConversationId && submissionFlightsRef.current.has(targetConversationId))) return;
     setAttachmentsByDraftKey((current) => {
       const attachment = current[draftKey]?.find((item) => item.id === id);
       if (attachment) URL.revokeObjectURL(attachment.previewUrl);
@@ -349,7 +351,12 @@ export function CodingChatPanel({
     });
     uploadedAttachmentsRef.current.delete(id);
     uploadFlightsRef.current.delete(id);
-  }, [draftKey]);
+    setSubmissionErrors((current) => {
+      const next = { ...current };
+      delete next[draftKey];
+      return next;
+    });
+  }, [draftKey, targetConversationId]);
 
   const prepareAttachments = useCallback(async (
     attachments: LocalComposerAttachment[],
diff --git a/src/pages/Chat/CodingComposer.tsx b/src/pages/Chat/CodingComposer.tsx
index 55d9ae5..830f4ee 100644
--- a/src/pages/Chat/CodingComposer.tsx
+++ b/src/pages/Chat/CodingComposer.tsx
@@ -91,6 +91,7 @@ export function CodingComposer({
         type="file"
         accept="image/png,image/jpeg,image/webp,image/gif"
         multiple
+        disabled={!editable || submitting}
         className="sr-only"
         data-testid="coding-file-attachment-input"
         onChange={(event) => {
@@ -110,8 +111,9 @@ export function CodingComposer({
                 />
                 <button
                   type="button"
-                  className="absolute right-1 top-1 flex h-10 w-10 translate-x-2 -translate-y-2 items-end justify-start rounded-full bg-foreground/85 p-1.5 text-background transition-[background-color,scale] duration-150 ease-out hover:bg-foreground active:scale-[0.96]"
+                  className="absolute right-1 top-1 flex h-10 w-10 translate-x-2 -translate-y-2 items-end justify-start rounded-full bg-foreground/85 p-1.5 text-background transition-[background-color,scale] duration-150 ease-out hover:bg-foreground active:scale-[0.96] disabled:cursor-not-allowed disabled:opacity-60"
                   aria-label={`移除图片 ${attachment.name}`}
+                  disabled={submitting}
                   onClick={() => onRemoveAttachment(attachment.id)}
                 >
                   <X className="h-3.5 w-3.5" aria-hidden="true" />
@@ -133,6 +135,7 @@ export function CodingComposer({
             if (canSend) onSubmit();
           }}
           onPaste={(event) => {
+            if (submitting) return;
             const files = Array.from(event.clipboardData.files).filter((file) => file.type.startsWith('image/'));
             if (files.length > 0) onAddFiles(files);
           }}
diff --git a/src/stores/coding-conversations.ts b/src/stores/coding-conversations.ts
index 6b45c44..37b0b24 100644
--- a/src/stores/coding-conversations.ts
+++ b/src/stores/coding-conversations.ts
@@ -702,10 +702,12 @@ export function createCodingConversationStore(
         };
       });
 
+      let attachmentsPrepared = !input.prepareAttachments;
       try {
         if (input.prepareAttachments) {
           submittedDraft.attachments = (await input.prepareAttachments())
             .map((attachment) => ({ ...attachment }));
+          attachmentsPrepared = true;
           set((state) => {
             const currentEntry = state.entriesByConversationId[input.conversationId] ?? emptyEntry();
             const requests = state.requestsByConversationId[input.conversationId] ?? {};
@@ -765,6 +767,7 @@ export function createCodingConversationStore(
       } catch (error) {
         const failure = errorDetails(error);
         const uncertain = failure.code === 'CODING_REQUEST_UNCERTAIN';
+        const preSubmitFailure = !attachmentsPrepared;
         set((state) => {
           const currentEntry = state.entriesByConversationId[input.conversationId] ?? emptyEntry();
           const requests = state.requestsByConversationId[input.conversationId] ?? {};
@@ -776,7 +779,11 @@ export function createCodingConversationStore(
           const reducer = uncertain
             ? currentEntry.reducer
             : withRejectedNode(currentEntry.reducer, nodeId);
-          const nextEntry = { ...currentEntry, reducer, error: failure.message };
+          const nextEntry = {
+            ...currentEntry,
+            reducer,
+            error: preSubmitFailure ? currentEntry.error : failure.message,
+          };
           return {
             entriesByConversationId: {
               ...state.entriesByConversationId,
diff --git a/tests/unit/coding-attachments-routes.test.ts b/tests/unit/coding-attachments-routes.test.ts
index 02408db..a73e621 100644
--- a/tests/unit/coding-attachments-routes.test.ts
+++ b/tests/unit/coding-attachments-routes.test.ts
@@ -3,7 +3,7 @@ import { once } from 'node:events';
 import { mkdtemp, rm } from 'node:fs/promises';
 import { tmpdir } from 'node:os';
 import path from 'node:path';
-import { afterEach, describe, expect, it } from 'vitest';
+import { afterEach, describe, expect, it, vi } from 'vitest';
 import { handleCodingAttachmentRoutes } from '../../electron/api/routes/coding-attachments';
 import { getHostApiToken, startHostApiServer } from '../../electron/api/server';
 import { CodingAttachmentStore } from '../../electron/coding-projects/attachment-store';
@@ -44,6 +44,37 @@ async function startAttachmentServer(maxBytes = 16 * 1024 * 1024) {
   };
 }
 
+async function startAttachmentFailureServer() {
+  const attachments = {
+    put: vi.fn(async () => {
+      throw new Error('write failed');
+    }),
+    read: vi.fn(async () => {
+      throw new Error('read failed');
+    }),
+  };
+  const context = { codingProducts: { attachments } } as unknown as HostApiContext;
+  const server = createServer((request, response) => {
+    const url = new URL(request.url ?? '/', 'http://127.0.0.1');
+    void handleCodingAttachmentRoutes(request, response, url, context).then((handled) => {
+      if (!handled) {
+        response.statusCode = 404;
+        response.end();
+      }
+    });
+  });
+  await new Promise<void>((resolve) => server.listen(0, '127.0.0.1', resolve));
+  const address = server.address();
+  if (!address || typeof address === 'string') throw new Error('Attachment test server failed');
+  return {
+    baseUrl: `http://127.0.0.1:${address.port}`,
+    close: async () => await new Promise<void>((resolve, reject) => {
+      server.closeAllConnections();
+      server.close((error) => error ? reject(error) : resolve());
+    }),
+  };
+}
+
 async function startAuthenticatedHostServer() {
   const root = await mkdtemp(path.join(tmpdir(), 'makelore-coding-host-attachments-'));
   roots.push(root);
@@ -222,7 +253,33 @@ describe('coding attachment routes', () => {
       );
       expect(response.status).toBe(413);
       expect(response.body).toMatchObject({
-        code: 'CODING_ATTACHMENT_TOO_LARGE',
+        code: 'CODING_ATTACHMENT_INVALID',
+      });
+    } finally {
+      await server.close();
+    }
+  });
+
+  it('uses registered errors for unreadable content and upload storage failures', async () => {
+    const server = await startAttachmentFailureServer();
+    try {
+      const content = await fetch(
+        `${server.baseUrl}/api/coding/attachments/attachment-1/content`,
+      );
+      expect(content.status).toBe(404);
+      await expect(content.json()).resolves.toMatchObject({
+        code: 'CODING_ATTACHMENT_NOT_FOUND',
+      });
+
+      const upload = await fetch(`${server.baseUrl}/api/coding/attachments`, {
+        method: 'POST',
+        headers: { 'Content-Type': 'image/png' },
+        body: new Uint8Array([137, 80, 78, 71, 13, 10, 26, 10]),
+      });
+      expect(upload.status).toBe(500);
+      await expect(upload.json()).resolves.toMatchObject({
+        code: 'CODING_STORAGE_WRITE_FAILED',
+        error: '本地数据写入失败，请检查存储后重试。',
       });
     } finally {
       await server.close();
diff --git a/tests/unit/coding-chat-panel.test.tsx b/tests/unit/coding-chat-panel.test.tsx
index 59619c0..d2f6c11 100644
--- a/tests/unit/coding-chat-panel.test.tsx
+++ b/tests/unit/coding-chat-panel.test.tsx
@@ -365,6 +365,162 @@ describe('CodingChatPanel first Conversation', () => {
     expect(maxActiveUploads).toBeLessThanOrEqual(4);
   });
 
+  it('locks attachment removal while an upload is still pending', async () => {
+    const upload = deferred<{ attachmentId: string; mime: string; byteLength: number }>();
+    projectApi.list.mockResolvedValue({ projects: [project], activeProjectId: project.id });
+    projectApi.config.mockResolvedValue({ project, config });
+    projectApi.conversations.mockResolvedValue([conversation]);
+    conversationApi.events.mockResolvedValue(new FakeEventSource() as unknown as EventSource);
+    conversationApi.recover.mockResolvedValue(undefined);
+    conversationApi.submit.mockImplementation(async (input: {
+      conversationId: string;
+      clientRequestId: string;
+      mode: 'prompt';
+    }) => ({
+      accepted: true,
+      conversationId: input.conversationId,
+      clientRequestId: input.clientRequestId,
+      runId: 'run-1',
+      mode: input.mode,
+    }));
+    attachmentApi.upload.mockReturnValue(upload.promise);
+    const { CodingChatPanel } = await import('@/pages/Chat/CodingChatPanel');
+    const { createLocalConversationSnapshot } = await import('@/pages/Chat/coding-chat-snapshot');
+    const { codingConversationStore } = await import('@/stores/coding-conversations');
+    conversationApi.snapshot.mockResolvedValue(createLocalConversationSnapshot(project.id, conversation));
+    render(<CodingChatPanel />);
+    await screen.findByRole('textbox');
+    await waitFor(() => expect(codingConversationStore.getState().selectedConversationId)
+      .toBe(conversation.id));
+
+    const file = new File(['image'], 'held.png', { type: 'image/png' });
+    fireEvent.change(screen.getByTestId('coding-file-attachment-input'), {
+      target: { files: [file] },
+    });
+    fireEvent.click(await screen.findByRole('button', { name: '发送' }));
+    await waitFor(() => expect(attachmentApi.upload).toHaveBeenCalledOnce());
+
+    const remove = screen.getByRole('button', { name: '移除图片 held.png' });
+    expect(remove).toBeDisabled();
+    fireEvent.click(remove);
+    expect(screen.getByAltText('held.png')).toBeInTheDocument();
+
+    upload.resolve({ attachmentId: 'attachment-held', mime: 'image/png', byteLength: 5 });
+    await waitFor(() => expect(conversationApi.submit).toHaveBeenCalledOnce());
+    await waitFor(() => expect(screen.queryByAltText('held.png')).not.toBeInTheDocument());
+  });
+
+  it('keeps next-message images out of a submission while its 202 response is pending', async () => {
+    const acceptanceFlight = deferred<{
+      accepted: true;
+      conversationId: string;
+      clientRequestId: string;
+      runId: string;
+      mode: 'prompt';
+    }>();
+    projectApi.list.mockResolvedValue({ projects: [project], activeProjectId: project.id });
+    projectApi.config.mockResolvedValue({ project, config });
+    projectApi.conversations.mockResolvedValue([conversation]);
+    conversationApi.events.mockResolvedValue(new FakeEventSource() as unknown as EventSource);
+    conversationApi.recover.mockResolvedValue(undefined);
+    conversationApi.submit.mockReturnValue(acceptanceFlight.promise);
+    attachmentApi.upload.mockImplementation(async (file: File) => ({
+      attachmentId: `attachment-${file.name}`,
+      mime: file.type,
+      byteLength: file.size,
+    }));
+    const { CodingChatPanel } = await import('@/pages/Chat/CodingChatPanel');
+    const { createLocalConversationSnapshot } = await import('@/pages/Chat/coding-chat-snapshot');
+    const { codingConversationStore } = await import('@/stores/coding-conversations');
+    conversationApi.snapshot.mockResolvedValue(createLocalConversationSnapshot(project.id, conversation));
+    render(<CodingChatPanel />);
+    const textbox = await screen.findByRole('textbox');
+    await waitFor(() => expect(codingConversationStore.getState().selectedConversationId)
+      .toBe(conversation.id));
+
+    const first = new File(['first'], 'first.png', { type: 'image/png' });
+    const next = new File(['next'], 'next.png', { type: 'image/png' });
+    fireEvent.change(screen.getByTestId('coding-file-attachment-input'), {
+      target: { files: [first] },
+    });
+    fireEvent.click(await screen.findByRole('button', { name: '发送' }));
+    await waitFor(() => expect(conversationApi.submit).toHaveBeenCalledOnce());
+    expect(screen.getByTestId('coding-file-attachment-input')).toBeDisabled();
+
+    fireEvent.paste(textbox, { clipboardData: { files: [next] } });
+    expect(screen.queryByAltText('next.png')).not.toBeInTheDocument();
+    expect(attachmentApi.upload).toHaveBeenCalledOnce();
+
+    acceptanceFlight.resolve({
+      accepted: true,
+      conversationId: conversation.id,
+      clientRequestId: 'request-1',
+      runId: 'run-1',
+      mode: 'prompt',
+    });
+    await waitFor(() => expect(screen.getByTestId('coding-file-attachment-input')).toBeEnabled());
+    fireEvent.paste(textbox, { clipboardData: { files: [next] } });
+    expect(await screen.findByAltText('next.png')).toBeInTheDocument();
+    expect(attachmentApi.upload).toHaveBeenCalledOnce();
+  });
+
+  it('keeps attachment validation failures local and reuses successful uploads on retry', async () => {
+    projectApi.list.mockResolvedValue({ projects: [project], activeProjectId: project.id });
+    projectApi.config.mockResolvedValue({ project, config });
+    projectApi.conversations.mockResolvedValue([conversation]);
+    conversationApi.events.mockResolvedValue(new FakeEventSource() as unknown as EventSource);
+    conversationApi.recover.mockResolvedValue(undefined);
+    conversationApi.submit.mockImplementation(async (input: {
+      conversationId: string;
+      clientRequestId: string;
+      mode: 'prompt';
+    }) => ({
+      accepted: true,
+      conversationId: input.conversationId,
+      clientRequestId: input.clientRequestId,
+      runId: 'run-1',
+      mode: input.mode,
+    }));
+    attachmentApi.upload.mockImplementation(async (file: File) => {
+      if (file.name === 'invalid.png') throw new Error('图片附件无效。');
+      return {
+        attachmentId: `attachment-${file.name}`,
+        mime: file.type,
+        byteLength: file.size,
+      };
+    });
+    const { CodingChatPanel } = await import('@/pages/Chat/CodingChatPanel');
+    const { createLocalConversationSnapshot } = await import('@/pages/Chat/coding-chat-snapshot');
+    const { codingConversationStore } = await import('@/stores/coding-conversations');
+    conversationApi.snapshot.mockResolvedValue(createLocalConversationSnapshot(project.id, conversation));
+    render(<CodingChatPanel />);
+    await screen.findByRole('textbox');
+    await waitFor(() => expect(codingConversationStore.getState().selectedConversationId)
+      .toBe(conversation.id));
+
+    const valid = new File(['valid'], 'valid.png', { type: 'image/png' });
+    const invalid = new File(['invalid'], 'invalid.png', { type: 'image/png' });
+    fireEvent.change(screen.getByTestId('coding-file-attachment-input'), {
+      target: { files: [valid, invalid] },
+    });
+    fireEvent.click(await screen.findByRole('button', { name: '发送' }));
+
+    expect(await screen.findByText('图片附件无效。')).toBeInTheDocument();
+    expect(codingConversationStore.getState().entriesByConversationId[conversation.id]?.error)
+      .toBeNull();
+    expect(screen.queryByRole('button', { name: '重试' })).not.toBeInTheDocument();
+    expect(screen.getByRole('button', { name: '发送' })).toBeEnabled();
+    fireEvent.click(screen.getByRole('button', { name: '移除图片 invalid.png' }));
+    await waitFor(() => expect(screen.queryByText('图片附件无效。')).not.toBeInTheDocument());
+
+    fireEvent.click(screen.getByRole('button', { name: '发送' }));
+    await waitFor(() => expect(conversationApi.submit).toHaveBeenCalledOnce());
+    expect(attachmentApi.upload.mock.calls.filter(([file]) => file.name === 'valid.png'))
+      .toHaveLength(1);
+    expect(attachmentApi.upload).toHaveBeenCalledTimes(2);
+    expect(conversationApi.recover).not.toHaveBeenCalled();
+  });
+
   it('shows the 202 acceptance and preserves Enter versus Shift+Enter behavior', async () => {
     const { CodingComposer } = await import('@/pages/Chat/CodingComposer');
     const onSubmit = vi.fn();
diff --git a/tests/unit/coding-conversations-store.test.tsx b/tests/unit/coding-conversations-store.test.tsx
index 7025054..bf25e1a 100644
--- a/tests/unit/coding-conversations-store.test.tsx
+++ b/tests/unit/coding-conversations-store.test.tsx
@@ -429,6 +429,55 @@ describe('coding Conversation store', () => {
       .toMatchObject({ id: 'node-1', status: 'error' });
   });
 
+  it('keeps attachment preparation failures out of runtime recovery and permits a direct retry', async () => {
+    const recover = vi.fn(async () => undefined);
+    const submitPrompt = vi.fn(async (input) => acceptance(
+      input.conversationId,
+      input.clientRequestId,
+    ));
+    const store = createCodingConversationStore({
+      getSnapshot: vi.fn(),
+      openEvents: vi.fn(),
+      submitPrompt,
+      recover,
+      createId: ids(),
+    });
+    store.getState().applySnapshotEvent(snapshotEvent(snapshot('conversation-a')));
+    store.getState().setDraft('conversation-a', 'Inspect the image');
+
+    await expect(store.getState().submitPrompt({
+      conversationId: 'conversation-a',
+      mode: 'prompt',
+      prepareAttachments: async () => {
+        throw new AppError('VALIDATION', '图片附件无效。', undefined, {
+          backendCode: 'CODING_ATTACHMENT_INVALID',
+        });
+      },
+    })).rejects.toThrow('图片附件无效。');
+
+    expect(store.getState().entriesByConversationId['conversation-a']).toMatchObject({
+      loadState: 'live',
+      error: null,
+    });
+    expect(store.getState().draftsByConversationId['conversation-a'].text)
+      .toBe('Inspect the image');
+    expect(store.getState().requestsByConversationId['conversation-a']['request-1'])
+      .toMatchObject({ status: 'rejected', errorCode: 'CODING_ATTACHMENT_INVALID' });
+    expect(submitPrompt).not.toHaveBeenCalled();
+    expect(recover).not.toHaveBeenCalled();
+
+    await store.getState().submitPrompt({
+      conversationId: 'conversation-a',
+      mode: 'prompt',
+      prepareAttachments: async () => [{
+        attachmentId: 'attachment-valid',
+        mime: 'image/png',
+        previewUrl: 'blob:valid',
+      }],
+    });
+    expect(submitPrompt).toHaveBeenCalledOnce();
+  });
+
   it('keeps an uncertain optimistic request recoverable without replaying it on reconnect', async () => {
     const source = new FakeEventSource();
     const submitPrompt = vi.fn(async () => {