diff --git a/par-core/src/main/java/com/par/core/adapter/AdapterEngine.java b/par-core/src/main/java/com/par/core/adapter/AdapterEngine.java
index b333c9d..ba5c758 100644
--- a/par-core/src/main/java/com/par/core/adapter/AdapterEngine.java
+++ b/par-core/src/main/java/com/par/core/adapter/AdapterEngine.java
@@ -48,26 +48,24 @@ public class AdapterEngine {
             result.put("matched", true);
             result.put("pageName", "JSON响应");
 
+            List<Map<String, Object>> rows = new ArrayList<>();
+
             if (parsed instanceof Map) {
                 @SuppressWarnings("unchecked")
                 Map<String, Object> map = (Map<String, Object>) parsed;
                 result.put("message", "JSON 对象，共 " + map.size() + " 个顶层字段");
-                // 展示顶层字段
-                List<Map<String, Object>> rows = new ArrayList<>();
                 Map<String, Object> row = new LinkedHashMap<>();
                 for (String key : map.keySet()) {
                     Object val = map.get(key);
-                    row.put(key, val instanceof String ? val : objectMapper.writeValueAsString(val));
+                    row.put(key, toDisplayString(val));
                 }
                 rows.add(row);
-                result.put("extracted", rows);
                 result.put("rowCount", 1);
                 result.put("fieldCount", map.size());
             } else if (parsed instanceof List) {
                 @SuppressWarnings("unchecked")
                 List<Object> list = (List<Object>) parsed;
                 result.put("message", "JSON 数组，共 " + list.size() + " 条记录");
-                List<Map<String, Object>> rows = new ArrayList<>();
                 int max = Math.min(list.size(), 20);
                 for (int i = 0; i < max; i++) {
                     Object item = list.get(i);
@@ -76,18 +74,26 @@ public class AdapterEngine {
                         @SuppressWarnings("unchecked")
                         Map<String, Object> m = (Map<String, Object>) item;
                         for (String key : m.keySet()) {
-                            Object val = m.get(key);
-                            row.put(key, val instanceof String ? val : objectMapper.writeValueAsString(val));
+                            row.put(key, toDisplayString(m.get(key)));
                         }
                     } else {
                         row.put("value", item);
                     }
                     rows.add(row);
                 }
-                result.put("extracted", rows);
                 result.put("rowCount", list.size());
                 result.put("fieldCount", rows.isEmpty() ? 0 : rows.get(0).size());
+            } else {
+                // 简单值（string/number/boolean/null）
+                result.put("message", "JSON 简单值");
+                Map<String, Object> row = new LinkedHashMap<>();
+                row.put("value", parsed);
+                rows.add(row);
+                result.put("rowCount", 1);
+                result.put("fieldCount", 1);
             }
+
+            result.put("extracted", rows);
         } catch (Exception e) {
             result.put("contentType", "json");
             result.put("matched", false);
@@ -282,4 +288,12 @@ public class AdapterEngine {
         if (s.equals("false") || s.equals("no") || s.equals("0") || s.equals("否")) return false;
         return null;
     }
+
+    /** 值转展示字符串（嵌套对象序列化，null → "null"） */
+    private String toDisplayString(Object val) {
+        if (val == null) return "null";
+        if (val instanceof String s) return s;
+        if (val instanceof Number || val instanceof Boolean) return val.toString();
+        try { return objectMapper.writeValueAsString(val); } catch (Exception e) { return val.toString(); }
+    }
 }