diff --git a/backend/internal/util/string.go b/backend/internal/util/string.go
new file mode 100644
index 0000000..460be86
--- /dev/null
+++ b/backend/internal/util/string.go
@@ -0,0 +1,9 @@
+package util
+
+// Truncate 截断字符串到指定长度，超出部分用 "..." 替换
+func Truncate(s string, maxLen int) string {
+	if len(s) <= maxLen {
+		return s
+	}
+	return s[:maxLen] + "..."
+}