diff --git a/cmd/ohos/HomeAgent/entry/src/main/ets/common/AttachmentImage.ets b/cmd/ohos/HomeAgent/entry/src/main/ets/common/AttachmentImage.ets
new file mode 100644
index 0000000..4bac3fc
--- /dev/null
+++ b/cmd/ohos/HomeAgent/entry/src/main/ets/common/AttachmentImage.ets
@@ -0,0 +1,37 @@
+/**
+ * 附件的字节获取与解码（网络 / 沙箱 I/O）。
+ *
+ * 字节走 GET <base>/files/<name> 或 /uploads/<name>（注意不带 /api/v1 前缀）。
+ * 这两条路由在后端是 requireWeb，但对 API Key 客户端同等放行，
+ * 所以带上和普通接口一样的鉴权头即可，无需 web 登录态。
+ *
+ * 从 components/Attachment.ets 抽出：缩略图与详情大图都走同一条解码路径。
+ */
+
+import { image } from '@kit.ImageKit';
+import { fileIo } from '@kit.CoreFileKit';
+import { apiClient } from './ApiClient';
+
+/** 下载并解码成 PixelMap；任何一步失败都返回 undefined（调用方显示占位）。 */
+export async function loadPixelMap(url: string): Promise<image.PixelMap | undefined> {
+  try {
+    // 本地待上传的图片：直接读沙箱文件，不走网络
+    if (url.startsWith('file://')) {
+      const path: string = url.substring(7);
+      const f = fileIo.openSync(path, fileIo.OpenMode.READ_ONLY);
+      const localSrc: image.ImageSource = image.createImageSource(f.fd);
+      const localPm: image.PixelMap = await localSrc.createPixelMap();
+      await localSrc.release();
+      fileIo.closeSync(f);
+      return localPm;
+    }
+    const abs: string = apiClient.absoluteUrl(url);
+    const resp = await apiClient.getBinary(abs, 15000);
+    const src: image.ImageSource = image.createImageSource(resp.data);
+    const pm: image.PixelMap = await src.createPixelMap();
+    await src.release();
+    return pm;
+  } catch (e) {
+    return undefined;
+  }
+}
diff --git a/cmd/ohos/HomeAgent/entry/src/main/ets/common/AttachmentMeta.ets b/cmd/ohos/HomeAgent/entry/src/main/ets/common/AttachmentMeta.ets
new file mode 100644
index 0000000..33f671a
--- /dev/null
+++ b/cmd/ohos/HomeAgent/entry/src/main/ets/common/AttachmentMeta.ets
@@ -0,0 +1,103 @@
+/**
+ * 附件的解析与格式化（纯函数，无 UI、无平台 I/O）。
+ *
+ * 后端 Attachment 只有四个字段：type / url / size / name
+ * （internal/plugins/webui/handler.go），没有 mime、没有像素尺寸、没有本地路径。
+ * 所以详情页里的"尺寸/格式"必须由客户端自己解码得出，不能假装后端给了。
+ *
+ * 从 components/Attachment.ets 抽出：附件卡与附件详情都要用这几个函数，
+ * 放在 common 里两边共用，也不必让 UI 文件承担这段纯逻辑。
+ */
+
+import { ChatAttachment } from '../model/Model';
+
+/** 从后端 JSON 里解析 attachment 字段；缺字段或类型不对则返回 undefined。 */
+export function parseAttachment(raw: Object | undefined): ChatAttachment | undefined {
+  if (raw === undefined || raw === null) {
+    return undefined;
+  }
+  const o: Record<string, Object> = raw as Record<string, Object>;
+  const url: string = o['url'] as string ?? '';
+  if (url.length === 0) {
+    return undefined;
+  }
+  const t: string = o['type'] as string ?? 'file';
+  const a: ChatAttachment = {
+    type: t === 'image' ? 'image' : 'file',
+    url: url,
+    size: o['size'] as number ?? 0,
+    name: o['name'] as string ?? fileNameOf(url),
+  };
+  return a;
+}
+
+/** 由 SSE channel_output 事件构造附件（字段名与 history 不同）。 */
+export function attachmentFromChannelOutput(
+  outputType: string, url: string, size: number): ChatAttachment | undefined {
+  if (url.length === 0) {
+    return undefined;
+  }
+  if (outputType !== 'image' && outputType !== 'file') {
+    return undefined;
+  }
+  const a: ChatAttachment = {
+    type: outputType,
+    url: url,
+    size: size,
+    name: fileNameOf(url),
+  };
+  return a;
+}
+
+/** 取 URL 最后一段作为展示文件名，与后端 handler.go 的取名方式一致。 */
+export function fileNameOf(url: string): string {
+  let s: string = url;
+  const q: number = s.indexOf('?');
+  if (q >= 0) {
+    s = s.substring(0, q);
+  }
+  const i: number = s.lastIndexOf('/');
+  const name: string = i >= 0 ? s.substring(i + 1) : s;
+  return name.length > 0 ? name : '附件';
+}
+
+/** 人类可读字节数，口径对齐后端 formatBytes（KB 以上保留一位小数）。 */
+export function formatBytes(n: number): string {
+  if (n <= 0) {
+    return '';
+  }
+  if (n < 1024) {
+    return n.toString() + ' B';
+  }
+  const kb: number = n / 1024;
+  if (kb < 1024) {
+    return oneDecimal(kb) + ' KB';
+  }
+  const mb: number = kb / 1024;
+  if (mb < 1024) {
+    return oneDecimal(mb) + ' MB';
+  }
+  return oneDecimal(mb / 1024) + ' GB';
+}
+
+function oneDecimal(v: number): string {
+  return (Math.round(v * 10) / 10).toString();
+}
+
+/** 由文件名后缀猜测类型标签。后端不返回 mime，只能这样标注。 */
+export function extLabel(name: string): string {
+  const i: number = name.lastIndexOf('.');
+  if (i < 0 || i === name.length - 1) {
+    return '未知类型';
+  }
+  return name.substring(i + 1).toUpperCase();
+}
+
+/** 去掉路径分隔符，避免附件名把文件写到 filesDir 之外。 */
+export function sanitize(name: string): string {
+  let s: string = name.replace(/[\/\\:*?"<>|]/g, '_');
+  if (s.length === 0) {
+    s = 'attachment';
+  }
+  return s;
+}
diff --git a/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatHistory.ets b/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatHistory.ets
index 432d806..165ae1c 100644
--- a/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatHistory.ets
+++ b/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatHistory.ets
@@ -6,7 +6,7 @@
  */
 
 import { ChatMessage, ToolCallInfo, ChatAttachment } from '../model/Model';
-import { parseAttachment } from '../components/Attachment';
+import { parseAttachment } from './AttachmentMeta';
 import { stringifyField } from './ChatFormat';
 
 /** 分页历史解析结果：消息列表 + 服务端分页元数据 */
diff --git a/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatSession.ets b/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatSession.ets
index 02225ee..0fb5122 100644
--- a/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatSession.ets
+++ b/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatSession.ets
@@ -10,7 +10,7 @@ import { apiClient } from './ApiClient';
 import { connStore } from './ConnStore';
 import { userMessage, isTimeout } from './UserError';
 import { chatStore } from './ChatStore';
-import { parseAttachment } from '../components/Attachment';
+import { parseAttachment } from './AttachmentMeta';
 import { http } from '@kit.NetworkKit';
 
 interface SendChatBody {
diff --git a/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatSse.ets b/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatSse.ets
index cb34c39..a387ecb 100644
--- a/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatSse.ets
+++ b/cmd/ohos/HomeAgent/entry/src/main/ets/common/ChatSse.ets
@@ -7,7 +7,7 @@
  */
 
 import { ChatMessage, ToolCallInfo, ChatAttachment } from '../model/Model';
-import { attachmentFromChannelOutput } from '../components/Attachment';
+import { attachmentFromChannelOutput } from './AttachmentMeta';
 import { SseEvent } from './SseClient';
 import { stringifyField } from './ChatFormat';
 import { hilog } from '@kit.PerformanceAnalysisKit';
diff --git a/cmd/ohos/HomeAgent/entry/src/main/ets/components/Attachment.ets b/cmd/ohos/HomeAgent/entry/src/main/ets/components/Attachment.ets
index 9ff7f6a..b5fb27b 100644
--- a/cmd/ohos/HomeAgent/entry/src/main/ets/components/Attachment.ets
+++ b/cmd/ohos/HomeAgent/entry/src/main/ets/components/Attachment.ets
@@ -4,107 +4,20 @@ import { common } from '@kit.AbilityKit';
 import { apiClient } from '../common/ApiClient';
 import { userMessage } from '../common/UserError';
 import { ChatAttachment } from '../model/Model';
+import { extLabel, formatBytes, sanitize } from '../common/AttachmentMeta';
+import { loadPixelMap } from '../common/AttachmentImage';
 import { ThemePalette, DARK_PALETTE, LIGHT_PALETTE, RADIUS_LG, RADIUS_MD, RADIUS_SM, ANIM_FAST, ANIM_NORMAL, ANIM_ENTER } from '../common/Constants';
 import { COLOR_ERROR } from '../common/Constants';
 import { MotionBase } from './MotionBase';
 import { PlainCard } from './SubPage';
 
 /**
- * 附件解析与展示。
+ * 附件 UI：气泡内的附件卡 + 附件详情二级页内容。
  *
- * 后端 Attachment 只有四个字段：type / url / size / name
- * （internal/plugins/webui/handler.go），没有 mime、没有像素尺寸、没有本地路径。
- * 所以详情页里的"尺寸/格式"必须由客户端自己解码得出，不能假装后端给了。
+ * 解析/格式化（parseAttachment、formatBytes、extLabel…）在 common/AttachmentMeta.ets，
+ * 字节获取与解码在 common/AttachmentImage.ets —— 这里只留 UI。
  *
- * 字节走 GET <base>/files/<name> 或 /uploads/<name>（注意不带 /api/v1 前缀）。
- * 这两条路由在后端是 requireWeb，但对 API Key 客户端同等放行，
- * 所以带上和普通接口一样的鉴权头即可，无需 web 登录态。
- */
-
-/** 从后端 JSON 里解析 attachment 字段；缺字段或类型不对则返回 undefined。 */
-export function parseAttachment(raw: Object | undefined): ChatAttachment | undefined {
-  if (raw === undefined || raw === null) {
-    return undefined;
-  }
-  const o: Record<string, Object> = raw as Record<string, Object>;
-  const url: string = o['url'] as string ?? '';
-  if (url.length === 0) {
-    return undefined;
-  }
-  const t: string = o['type'] as string ?? 'file';
-  const a: ChatAttachment = {
-    type: t === 'image' ? 'image' : 'file',
-    url: url,
-    size: o['size'] as number ?? 0,
-    name: o['name'] as string ?? fileNameOf(url),
-  };
-  return a;
-}
-
-/** 由 SSE channel_output 事件构造附件（字段名与 history 不同）。 */
-export function attachmentFromChannelOutput(
-  outputType: string, url: string, size: number): ChatAttachment | undefined {
-  if (url.length === 0) {
-    return undefined;
-  }
-  if (outputType !== 'image' && outputType !== 'file') {
-    return undefined;
-  }
-  const a: ChatAttachment = {
-    type: outputType,
-    url: url,
-    size: size,
-    name: fileNameOf(url),
-  };
-  return a;
-}
-
-/** 取 URL 最后一段作为展示文件名，与后端 handler.go 的取名方式一致。 */
-export function fileNameOf(url: string): string {
-  let s: string = url;
-  const q: number = s.indexOf('?');
-  if (q >= 0) {
-    s = s.substring(0, q);
-  }
-  const i: number = s.lastIndexOf('/');
-  const name: string = i >= 0 ? s.substring(i + 1) : s;
-  return name.length > 0 ? name : '附件';
-}
-
-/** 人类可读字节数，口径对齐后端 formatBytes（KB 以上保留一位小数）。 */
-export function formatBytes(n: number): string {
-  if (n <= 0) {
-    return '';
-  }
-  if (n < 1024) {
-    return n.toString() + ' B';
-  }
-  const kb: number = n / 1024;
-  if (kb < 1024) {
-    return oneDecimal(kb) + ' KB';
-  }
-  const mb: number = kb / 1024;
-  if (mb < 1024) {
-    return oneDecimal(mb) + ' MB';
-  }
-  return oneDecimal(mb / 1024) + ' GB';
-}
-
-function oneDecimal(v: number): string {
-  return (Math.round(v * 10) / 10).toString();
-}
-
-/** 由文件名后缀猜测类型标签。后端不返回 mime，只能这样标注。 */
-export function extLabel(name: string): string {
-  const i: number = name.lastIndexOf('.');
-  if (i < 0 || i === name.length - 1) {
-    return '未知类型';
-  }
-  return name.substring(i + 1).toUpperCase();
-}
-
-/**
- * 气泡内的附件卡：图片显示缩略图，文件显示一枚文件条。
+ * 附件卡：图片显示缩略图，文件显示一枚文件条。
  * 点击进入附件详情二级页面（WebGUI 是新开标签页，移动端改为二级页）。
  */
 @Component
@@ -428,36 +341,3 @@ export struct AttachmentDetailContent {
     return this.isDark ? DARK_PALETTE : LIGHT_PALETTE;
   }
 }
-
-/** 下载并解码成 PixelMap；任何一步失败都返回 undefined（调用方显示占位）。 */
-async function loadPixelMap(url: string): Promise<image.PixelMap | undefined> {
-  try {
-    // 本地待上传的图片：直接读沙箱文件，不走网络
-    if (url.startsWith('file://')) {
-      const path: string = url.substring(7);
-      const f = fileIo.openSync(path, fileIo.OpenMode.READ_ONLY);
-      const localSrc: image.ImageSource = image.createImageSource(f.fd);
-      const localPm: image.PixelMap = await localSrc.createPixelMap();
-      await localSrc.release();
-      fileIo.closeSync(f);
-      return localPm;
-    }
-    const abs: string = apiClient.absoluteUrl(url);
-    const resp = await apiClient.getBinary(abs, 15000);
-    const src: image.ImageSource = image.createImageSource(resp.data);
-    const pm: image.PixelMap = await src.createPixelMap();
-    await src.release();
-    return pm;
-  } catch (e) {
-    return undefined;
-  }
-}
-
-/** 去掉路径分隔符，避免附件名把文件写到 filesDir 之外。 */
-function sanitize(name: string): string {
-  let s: string = name.replace(/[\/\\:*?"<>|]/g, '_');
-  if (s.length === 0) {
-    s = 'attachment';
-  }
-  return s;
-}
diff --git a/cmd/ohos/HomeAgent/entry/src/main/ets/components/ChatAttachBar.ets b/cmd/ohos/HomeAgent/entry/src/main/ets/components/ChatAttachBar.ets
index 635cd21..c361890 100644
--- a/cmd/ohos/HomeAgent/entry/src/main/ets/components/ChatAttachBar.ets
+++ b/cmd/ohos/HomeAgent/entry/src/main/ets/components/ChatAttachBar.ets
@@ -8,7 +8,7 @@
 import { ThemePalette, DARK_PALETTE, LIGHT_PALETTE, RADIUS_MD, RADIUS_PILL,
   ANIM_NORMAL } from '../common/Constants';
 import { MotionBase } from './MotionBase';
-import { formatBytes } from './Attachment';
+import { formatBytes } from '../common/AttachmentMeta';
 
 /** 加号菜单：两枚独立的玻璃胶囊，和输入区其他组件同一套视觉语言 */
 @Component
diff --git a/cmd/ohos/HomeAgent/entry/src/main/ets/components/ChatComposer.ets b/cmd/ohos/HomeAgent/entry/src/main/ets/components/ChatComposer.ets
index d8145b4..a0026e3 100644
--- a/cmd/ohos/HomeAgent/entry/src/main/ets/components/ChatComposer.ets
+++ b/cmd/ohos/HomeAgent/entry/src/main/ets/components/ChatComposer.ets
@@ -16,7 +16,7 @@ import { ThemePalette, DARK_PALETTE, LIGHT_PALETTE, ANIM_FAST, ANIM_NORMAL } fro
 import { mimeOf } from '../common/ChatFormat';
 import { chatStore, K_CHAT_LOADING } from '../common/ChatStore';
 import { sendChatText, sendChatFile, interruptChat } from '../common/ChatSession';
-import { fileNameOf } from './Attachment';
+import { fileNameOf } from '../common/AttachmentMeta';
 import { ChatAttachMenu, ChatPendingChip } from './ChatAttachBar';
 import { NavFloatOverlay, FloatIconButton } from './PageTopBar';
 import { picker, fileIo } from '@kit.CoreFileKit';