diff --git a/electron/harness/tools/built-in/web-search.ts b/electron/harness/tools/built-in/web-search.ts
index 3573332..cbc13e6 100644
--- a/electron/harness/tools/built-in/web-search.ts
+++ b/electron/harness/tools/built-in/web-search.ts
@@ -247,19 +247,25 @@ export class WebSearchTool implements IMetonaTool {
   async execute(args: Record<string, unknown>, _context: ToolExecutionContext): Promise<unknown> {
     const query = args.query as string;
 
-    // 读取 SearXNG 配置（提前读取，使工具参数默认值与配置一致）
+    // 读取 SearXNG 配置
     const searxngConfig = this.readSearXNGConfig();
+    const useSearXNG = searxngConfig.enabled && !!searxngConfig.url;
 
-    // max_results: 仅由配置面板控制，AI 不可覆盖
-    const maxResults = Math.min(50, Math.max(1, searxngConfig.max_results > 0 ? searxngConfig.max_results : 30));
+    // 两个模式参数完全独立：
+    // - 内置模式：固定默认值 maxResults=30, fetchTop=5
+    // - SearXNG 模式：由配置面板控制
+    const maxResults = useSearXNG
+      ? Math.min(50, Math.max(1, searxngConfig.max_results > 0 ? searxngConfig.max_results : 30))
+      : 30;
 
     const timeRange = (args.time_range as string) ?? '';
     const enhanceSnippets = (args.enhance_snippets as boolean) ?? true;
 
-    // fetch_top: 仅由配置面板控制，AI 不可覆盖
-    const fetchTop = Math.min(8, Math.max(3, searxngConfig.fetch_count > 0 ? searxngConfig.fetch_count : 5));
+    const fetchTop = useSearXNG
+      ? Math.min(8, Math.max(3, searxngConfig.fetch_count > 0 ? searxngConfig.fetch_count : 5))
+      : 5;
 
-    logTool('web_search', `Config: maxResults=${maxResults}, fetchTop=${fetchTop}, searxng=${searxngConfig.enabled}`);
+    logTool('web_search', `Mode=${useSearXNG ? 'searxng' : 'builtin'}, maxResults=${maxResults}, fetchTop=${fetchTop}`);
 
     // 缓存检查（key 含模式 + maxResults + fetchTop，避免配置变更后返回旧缓存）
     const cacheKey = `${searxngConfig.enabled ? 'searxng' : 'builtin'}:${maxResults}:${fetchTop}:${normalizeUrl(query).toLowerCase()}`;
@@ -273,7 +279,7 @@ export class WebSearchTool implements IMetonaTool {
     let mode: string;
     let engineStats: Record<string, string>;
 
-    if (searxngConfig.enabled && searxngConfig.url) {
+    if (useSearXNG) {
       const searxResult = await this.searchSearXNG(query, searxngConfig, maxResults, timeRange);
       results = searxResult.results;
       mode = 'searxng';