diff --git a/agents-flex-core/src/main/java/com/agentsflex/core/util/StringUtil.java b/agents-flex-core/src/main/java/com/agentsflex/core/util/StringUtil.java
new file mode 100644
index 0000000..594c0a5
--- /dev/null
+++ b/agents-flex-core/src/main/java/com/agentsflex/core/util/StringUtil.java
@@ -0,0 +1,72 @@
+/*
+ *  Copyright (c) 2023-2025, Agents-Flex (fuhai999@gmail.com).
+ *  <p>
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *  <p>
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *  <p>
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package com.agentsflex.core.util;
+
+public class StringUtil {
+
+    public static boolean noText(String string) {
+        return !hasText(string);
+    }
+
+    public static boolean hasText(String string) {
+        return string != null && !string.isEmpty() && containsText(string);
+    }
+
+    public static boolean hasText(String... strings) {
+        for (String string : strings) {
+            if (!hasText(string)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private static boolean containsText(CharSequence str) {
+        for (int i = 0; i < str.length(); i++) {
+            if (!Character.isWhitespace(str.charAt(i))) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    public static String getFirstWithText(String... strings) {
+        if (strings == null) {
+            return null;
+        }
+        for (String str : strings) {
+            if (hasText(str)) {
+                return str;
+            }
+        }
+        return null;
+    }
+
+    public static boolean isJsonObject(String jsonString) {
+        if (noText(jsonString)) {
+            return false;
+        }
+
+        jsonString = jsonString.trim();
+        return jsonString.startsWith("{") && jsonString.endsWith("}");
+    }
+
+    public static boolean notJsonObject(String jsonString) {
+        return !isJsonObject(jsonString);
+    }
+
+
+}