diff --git a/frontend/src/app/workspace/chats/[thread_id]/page.tsx b/frontend/src/app/workspace/chats/[thread_id]/page.tsx
index 5ae61615..4f1dcf52 100644
--- a/frontend/src/app/workspace/chats/[thread_id]/page.tsx
+++ b/frontend/src/app/workspace/chats/[thread_id]/page.tsx
@@ -14,7 +14,6 @@ import {
   DevDialogTitle,
 } from "@/components/ui/dev-dialog";
 import { useSidebar } from "@/components/ui/sidebar";
-import { Skeleton } from "@/components/ui/skeleton";
 import {
   ArtifactFileDetail,
   ArtifactFileList,
@@ -27,7 +26,6 @@ import { InputBox } from "@/components/workspace/input-box";
 import { MessageList } from "@/components/workspace/messages";
 import { ThreadContext } from "@/components/workspace/messages/context";
 import { ThreadTitle } from "@/components/workspace/thread-title";
-import { TokenUsageIndicator } from "@/components/workspace/token-usage-indicator";
 import { Tooltip } from "@/components/workspace/tooltip";
 import { useSpecificChatMode } from "@/components/workspace/use-chat-mode";
 import { Welcome } from "@/components/workspace/welcome";
@@ -260,7 +258,6 @@ export default function ChatPage() {
                   )}
                 </div>
                 <div className="flex items-center justify-end gap-2 overflow-hidden">
-                  {/* <TokenUsageIndicator messages={thread.messages} /> */}
                   <DevTodoList
                     className="bg-white"
                     todos={thread.values.todos ?? []}
@@ -521,21 +518,3 @@ export default function ChatPage() {
     </ThreadContext.Provider>
   );
 }
-
-function InputBoxSkeleton() {
-  return (
-    <div className="w-full rounded-[20px] bg-[#FBFAFC] p-4 shadow-[0_0_20px_0_rgba(0,0,0,0.10)]">
-      <div className="flex flex-col gap-4">
-        <Skeleton className="h-6 w-[220px]" />
-        <Skeleton className="h-[120px] w-full rounded-[16px]" />
-        <div className="flex items-center justify-between">
-          <div className="flex items-center gap-2">
-            <Skeleton className="h-9 w-9 rounded-full" />
-            <Skeleton className="h-9 w-9 rounded-full" />
-          </div>
-          <Skeleton className="h-9 w-20 rounded-full" />
-        </div>
-      </div>
-    </div>
-  );
-}
diff --git a/frontend/src/components/workspace/artifacts/artifact-file-detail.tsx b/frontend/src/components/workspace/artifacts/artifact-file-detail.tsx
index dcee6279..28710582 100644
--- a/frontend/src/components/workspace/artifacts/artifact-file-detail.tsx
+++ b/frontend/src/components/workspace/artifacts/artifact-file-detail.tsx
@@ -34,7 +34,6 @@ import { CodeEditor } from "@/components/workspace/code-editor";
 import { useArtifactContent } from "@/core/artifacts/hooks";
 import { urlOfArtifact } from "@/core/artifacts/utils";
 import { useI18n } from "@/core/i18n/hooks";
-import { installSkill } from "@/core/skills/api";
 import { streamdownPlugins } from "@/core/streamdown";
 import { checkCodeFile, getFileName } from "@/core/utils/files";
 import { useMarkdownDownload } from "@/core/utils/markdown-download";
@@ -61,7 +60,7 @@ export function ArtifactFileDetail({
 }: {
   className?: string;
   filepath: string;
-  threadId: string;
+  threadId?: string;
 }) {
   const { t } = useI18n();
   const { artifacts, setOpen, select, fullscreen, setFullscreen } =
@@ -98,12 +97,18 @@ export function ArtifactFileDetail({
     return (language === "html" && !isWriteFile) || language === "markdown";
   }, [isWriteFile, language]);
   const artifactUrl = useMemo(() => {
+    if (!threadId) {
+      return "";
+    }
     return urlOfArtifact({ filepath, threadId });
   }, [filepath, threadId]);
   const artifactPreviewKind = useMemo(() => {
     return getArtifactPreviewKind(filepath);
   }, [filepath]);
   const artifactViewerSrcDoc = useMemo(() => {
+    if (!artifactUrl) {
+      return "";
+    }
     return buildArtifactViewerSrcDoc({
       artifactUrl,
       fileName,
@@ -113,7 +118,7 @@ export function ArtifactFileDetail({
   const { content } = useArtifactContent({
     threadId,
     filepath: filepathFromProps,
-    enabled: isCodeFile && !isWriteFile,
+    enabled: Boolean(threadId) && isCodeFile && !isWriteFile,
   });
 
   const displayContent = content ?? "";
@@ -126,7 +131,6 @@ export function ArtifactFileDetail({
   }, [artifacts]);
 
   const [viewMode, setViewMode] = useState<"code" | "preview">("code");
-  const [isInstalling, setIsInstalling] = useState(false);
   const [zoom, setZoom] = useState(80);
 
   // 是否可以转换为docx/pdf（仅markdown文件支持）
@@ -172,28 +176,6 @@ export function ArtifactFileDetail({
     }
   }, [previewable]);
 
-  const handleInstallSkill = useCallback(async () => {
-    if (isInstalling) return;
-
-    setIsInstalling(true);
-    try {
-      const result = await installSkill({
-        thread_id: threadId,
-        path: filepath,
-      });
-      if (result.success) {
-        toast.success(result.message);
-      } else {
-        toast.error(result.message ?? "Failed to install skill");
-      }
-    } catch (error) {
-      console.error("Failed to install skill:", error);
-      toast.error("Failed to install skill");
-    } finally {
-      setIsInstalling(false);
-    }
-  }, [threadId, filepath, isInstalling]);
-
   return (
     // 给滚动遮挡头部定位relative
     <Artifact
@@ -358,7 +340,7 @@ export function ArtifactFileDetail({
                     <a
                       href={urlOfArtifact({
                         filepath,
-                        threadId,
+                        threadId: threadId ?? "",
                         download: true,
                       })}
                       target="_blank"
diff --git a/frontend/src/components/workspace/artifacts/artifact-file-list.tsx b/frontend/src/components/workspace/artifacts/artifact-file-list.tsx
index 6f3e16da..6169ee22 100644
--- a/frontend/src/components/workspace/artifacts/artifact-file-list.tsx
+++ b/frontend/src/components/workspace/artifacts/artifact-file-list.tsx
@@ -29,7 +29,7 @@ export function ArtifactFileList({
 }: {
   className?: string;
   files: string[];
-  threadId: string;
+  threadId?: string;
 }) {
   const { t } = useI18n();
   const { select: selectArtifact, setOpen } = useArtifacts();
@@ -48,6 +48,7 @@ export function ArtifactFileList({
       e.stopPropagation();
       e.preventDefault();
 
+      if (!threadId) return;
       if (installingFile) return;
 
       setInstallingFile(filepath);
@@ -98,7 +99,7 @@ export function ArtifactFileList({
               {file.endsWith(".skill") && (
                 <Button
                   variant="ghost"
-                  disabled={installingFile === file}
+                  disabled={!threadId || installingFile === file}
                   onClick={(e) => handleInstallSkill(e, file)}
                 >
                   {installingFile === file ? (
@@ -109,20 +110,27 @@ export function ArtifactFileList({
                   {t.common.install}
                 </Button>
               )}
-              <a
-                href={urlOfArtifact({
-                  filepath: file,
-                  threadId: threadId,
-                  download: true,
-                })}
-                target="_blank"
-                onClick={(e) => e.stopPropagation()}
-              >
-                <Button variant="ghost">
+              {threadId ? (
+                <a
+                  href={urlOfArtifact({
+                    filepath: file,
+                    threadId,
+                    download: true,
+                  })}
+                  target="_blank"
+                  onClick={(e) => e.stopPropagation()}
+                >
+                  <Button variant="ghost">
+                    <DownloadIcon className="size-4" />
+                    {t.common.download}
+                  </Button>
+                </a>
+              ) : (
+                <Button variant="ghost" disabled>
                   <DownloadIcon className="size-4" />
                   {t.common.download}
                 </Button>
-              </a>
+              )}
             </CardAction>
           </CardHeader>
         </Card>
diff --git a/frontend/src/components/workspace/export-trigger.tsx b/frontend/src/components/workspace/export-trigger.tsx
index b75d4e45..4d0d807d 100644
--- a/frontend/src/components/workspace/export-trigger.tsx
+++ b/frontend/src/components/workspace/export-trigger.tsx
@@ -21,7 +21,7 @@ import type { AgentThread } from "@/core/threads/types";
 import { useThread } from "./messages/context";
 import { Tooltip } from "./tooltip";
 
-export function ExportTrigger({ threadId }: { threadId: string }) {
+export function ExportTrigger({ threadId }: { threadId?: string }) {
   const { t } = useI18n();
   const { thread } = useThread();
 
@@ -49,7 +49,7 @@ export function ExportTrigger({ threadId }: { threadId: string }) {
     [messages, thread.values, threadId, t],
   );
 
-  if (messages.length === 0) {
+  if (!threadId || messages.length === 0) {
     return null;
   }
 
diff --git a/frontend/src/components/workspace/messages/message-list.tsx b/frontend/src/components/workspace/messages/message-list.tsx
index c83194e2..69c08277 100644
--- a/frontend/src/components/workspace/messages/message-list.tsx
+++ b/frontend/src/components/workspace/messages/message-list.tsx
@@ -39,7 +39,7 @@ export function MessageList({
   paddingBottom = 160,
 }: {
   className?: string;
-  threadId: string;
+  threadId?: string;
   thread: UseStream<AgentThreadState>;
   /** When set (e.g. from onFinish), use instead of thread.messages so SSE end shows complete state. */
   messagesOverride?: Message[];
@@ -98,7 +98,9 @@ export function MessageList({
                     className="mb-4"
                   />
                 )}
-                <ArtifactFileList files={files} threadId={threadId} />
+                {threadId ? (
+                  <ArtifactFileList files={files} threadId={threadId} />
+                ) : null}
               </div>
             );
           } else if (group.type === "assistant:subagent") {
diff --git a/frontend/src/components/workspace/thread-title.tsx b/frontend/src/components/workspace/thread-title.tsx
index 642e4e6f..35e9b57e 100644
--- a/frontend/src/components/workspace/thread-title.tsx
+++ b/frontend/src/components/workspace/thread-title.tsx
@@ -40,6 +40,7 @@ export function ThreadTitle({
     t.pages.newChat,
     t.pages.untitled,
     t.pages.appName,
+    thread,
     thread?.isThreadLoading,
     thread?.values,
   ]);
diff --git a/frontend/src/core/artifacts/hooks.ts b/frontend/src/core/artifacts/hooks.ts
index 4df9db70..6d875aba 100644
--- a/frontend/src/core/artifacts/hooks.ts
+++ b/frontend/src/core/artifacts/hooks.ts
@@ -11,7 +11,7 @@ export function useArtifactContent({
   enabled,
 }: {
   filepath: string;
-  threadId: string;
+  threadId?: string;
   enabled?: boolean;
 }) {
   const isWriteFile = useMemo(() => {
@@ -25,12 +25,17 @@ export function useArtifactContent({
     return null;
   }, [filepath, isWriteFile, thread]);
 
+  const canFetch = Boolean(threadId) && enabled !== false;
   const { data, isLoading, error } = useQuery({
     queryKey: ["artifact", filepath, threadId, isMock],
     queryFn: () => {
-      return loadArtifactContent({ filepath, threadId, isMock });
+      return loadArtifactContent({
+        filepath,
+        threadId: threadId ?? "",
+        isMock,
+      });
     },
-    enabled,
+    enabled: canFetch,
     // Cache artifact content for 5 minutes to avoid repeated fetches (especially for .skill ZIP extraction)
     staleTime: 5 * 60 * 1000,
   });
diff --git a/frontend/src/core/i18n/locales/en-US.ts b/frontend/src/core/i18n/locales/en-US.ts
index a03cc86f..12f68950 100644
--- a/frontend/src/core/i18n/locales/en-US.ts
+++ b/frontend/src/core/i18n/locales/en-US.ts
@@ -1,6 +1,5 @@
 import {
   CompassIcon,
-  GraduationCapIcon,
   ImageIcon,
   MicroscopeIcon,
   PenLineIcon,
diff --git a/frontend/src/core/threads/hooks.ts b/frontend/src/core/threads/hooks.ts
index c05310b8..eacd668a 100644
--- a/frontend/src/core/threads/hooks.ts
+++ b/frontend/src/core/threads/hooks.ts
@@ -456,7 +456,7 @@ export function useThreadStream({
                     : context.mode === "thinking"
                       ? "low"
                       : undefined),
-              thread_id: resolvedThreadId,
+              ...(resolvedThreadId ? { thread_id: resolvedThreadId } : {}),
             },
           },
         );
@@ -580,7 +580,7 @@ export function useSubmitThread({
           },
           context: {
             ...threadContext,
-            thread_id: threadId,
+            ...(threadId ? { thread_id: threadId } : {}),
           },
         },
       );
diff --git a/frontend/src/core/utils/markdown-download/converter.ts b/frontend/src/core/utils/markdown-download/converter.ts
index cd503ed4..df81bbb2 100644
--- a/frontend/src/core/utils/markdown-download/converter.ts
+++ b/frontend/src/core/utils/markdown-download/converter.ts
@@ -156,7 +156,6 @@ export async function downloadMarkdownAsPdf(
 // eslint-disable-next-line @typescript-eslint/no-unsafe-function-type
 async function loadHtml2Pdf(): Promise<Function> {
   const html2pdf = await import("html2pdf.js");
-  // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
   return html2pdf.default;
 }
 
diff --git a/frontend/src/hooks/use-selected-skill-listener.ts b/frontend/src/hooks/use-selected-skill-listener.ts
index fc20d66d..313a6cfd 100644
--- a/frontend/src/hooks/use-selected-skill-listener.ts
+++ b/frontend/src/hooks/use-selected-skill-listener.ts
@@ -25,7 +25,7 @@ interface SkillError {
 
 interface UseSelectedSkillListenerOptions {
   /** 当前会话 thread_id，用于调用 bootstrapRemoteSkill */
-  threadId: string | null;
+  threadId?: string | null;
 }
 
 interface UseSelectedSkillListenerReturn {