diff --git a/langgraph/src/components/ThreadSidebar.tsx b/langgraph/src/components/ThreadSidebar.tsx
index e16fef9..aa20170 100644
--- a/langgraph/src/components/ThreadSidebar.tsx
+++ b/langgraph/src/components/ThreadSidebar.tsx
@@ -37,6 +37,13 @@ function getLocalTitle(threadId: string): string | null {
   }
 }
 
+// Reject titles that look like UUIDs, short hashes, or empty strings
+const BAD_TITLE = /^[0-9a-f-]{8,}$/i;
+function sanitizeTitle(s: unknown): string | null {
+  if (typeof s !== "string" || !s.trim() || BAD_TITLE.test(s.trim())) return null;
+  return s.trim();
+}
+
 function groupByDate(threads: ThreadItem[]): { label: string; threads: ThreadItem[] }[] {
   const now = new Date();
   const groups: Record<string, ThreadItem[]> = {};
@@ -101,10 +108,10 @@ export function ThreadSidebar({
 
   const filtered = threads.filter((t) => {
     const label =
-      getLocalTitle(t.thread_id) ??
-      (t.metadata?.title as string) ??
-      (t.metadata?.firstMessage as string) ??
-      t.thread_id;
+      sanitizeTitle(getLocalTitle(t.thread_id)) ??
+      sanitizeTitle(t.metadata?.title) ??
+      sanitizeTitle(t.metadata?.firstMessage) ??
+      "新对话";
     return label.toLowerCase().includes(searchQuery.toLowerCase());
   });
 
@@ -190,9 +197,9 @@ export function ThreadSidebar({
             {groupThreads.map((t) => {
               const isActive = t.thread_id === currentThreadId;
               const itemLabel =
-                getLocalTitle(t.thread_id) ??
-                (t.metadata?.title as string) ??
-                (t.metadata?.firstMessage as string) ??
+                sanitizeTitle(getLocalTitle(t.thread_id)) ??
+                sanitizeTitle(t.metadata?.title) ??
+                sanitizeTitle(t.metadata?.firstMessage) ??
                 "新对话";
               const displayLabel = itemLabel.length > 16
                 ? itemLabel.slice(0, 16) + "…"