feat(search): add SearchProvider chain with keyless fallback (DuckDuckGo + SearXNG)

docker-compose.yml

@@ -25,6 +25,23 @@ services:
       timeout: 5s
       retries: 5
 
+  # SearXNG 搜索引擎（keyless 搜索 provider，零配置可用）
+  searxng:
+    image: searxng/searxng:latest
+    container_name: mateclaw-searxng
+    restart: unless-stopped
+    environment:
+      - SEARXNG_BASE_URL=http://searxng:8080
+    volumes:
+      - searxng_data:/etc/searxng
+    ports:
+      - "8088:8080"
+    healthcheck:
+      test: ["CMD", "wget", "--spider", "-q", "http://localhost:8080/healthz"]
+      interval: 30s
+      timeout: 5s
+      retries: 3
+
   # MateClaw 后端服务
   mateclaw-server:
     build:
@@ -35,6 +52,8 @@ services:
     depends_on:
       mysql:
         condition: service_healthy
+      searxng:
+        condition: service_healthy
     environment:
       SPRING_PROFILES_ACTIVE: mysql
       DB_HOST: mysql
@@ -52,3 +71,4 @@ services:
 volumes:
   mysql_data:
   server_data:
+  searxng_data:

mateclaw-server/src/main/java/vip/mate/system/model/SystemSettingsDTO.java

@@ -24,6 +24,12 @@ public class SystemSettingsDTO {
     private String tavilyApiKey;
     private String tavilyBaseUrl;
 
+    // ===== Keyless 搜索 provider 配置 =====
+    /** DuckDuckGo 是否启用（默认 true，作为零配置兜底） */
+    private Boolean duckduckgoEnabled;
+    /** SearXNG 实例地址（如 http://searxng:8080），为空则不使用 */
+    private String searxngBaseUrl;
+
     // 用于前端回显脱敏后的 API Key
     private String serperApiKeyMasked;
     private String tavilyApiKeyMasked;

mateclaw-server/src/main/java/vip/mate/system/service/SystemSettingService.java

@@ -24,6 +24,8 @@ public class SystemSettingService {
     private static final String SERPER_BASE_URL_KEY = "serperBaseUrl";
     private static final String TAVILY_API_KEY_KEY = "tavilyApiKey";
     private static final String TAVILY_BASE_URL_KEY = "tavilyBaseUrl";
+    private static final String DUCKDUCKGO_ENABLED_KEY = "duckduckgoEnabled";
+    private static final String SEARXNG_BASE_URL_KEY = "searxngBaseUrl";
 
     private final SystemSettingMapper systemSettingMapper;
 
@@ -40,6 +42,9 @@ public class SystemSettingService {
         dto.setSearchFallbackEnabled(Boolean.parseBoolean(getValue(SEARCH_FALLBACK_ENABLED_KEY, "false")));
         dto.setSerperBaseUrl(getValue(SERPER_BASE_URL_KEY, "https://google.serper.dev/search"));
         dto.setTavilyBaseUrl(getValue(TAVILY_BASE_URL_KEY, "https://api.tavily.com/search"));
+        // Keyless provider 配置
+        dto.setDuckduckgoEnabled(Boolean.parseBoolean(getValue(DUCKDUCKGO_ENABLED_KEY, "true")));
+        dto.setSearxngBaseUrl(getValue(SEARXNG_BASE_URL_KEY, ""));
         // API Key 脱敏回显
         dto.setSerperApiKeyMasked(maskApiKey(getValue(SERPER_API_KEY_KEY, "")));
         dto.setTavilyApiKeyMasked(maskApiKey(getValue(TAVILY_API_KEY_KEY, "")));
@@ -58,6 +63,8 @@ public class SystemSettingService {
         dto.setSerperBaseUrl(getValue(SERPER_BASE_URL_KEY, "https://google.serper.dev/search"));
         dto.setTavilyApiKey(getValue(TAVILY_API_KEY_KEY, ""));
         dto.setTavilyBaseUrl(getValue(TAVILY_BASE_URL_KEY, "https://api.tavily.com/search"));
+        dto.setDuckduckgoEnabled(Boolean.parseBoolean(getValue(DUCKDUCKGO_ENABLED_KEY, "true")));
+        dto.setSearxngBaseUrl(getValue(SEARXNG_BASE_URL_KEY, ""));
         return dto;
     }
 
@@ -90,6 +97,13 @@ public class SystemSettingService {
         if (dto.getTavilyBaseUrl() != null) {
             saveValue(TAVILY_BASE_URL_KEY, dto.getTavilyBaseUrl(), "Tavily 接口地址");
         }
+        // Keyless provider 配置
+        if (dto.getDuckduckgoEnabled() != null) {
+            saveValue(DUCKDUCKGO_ENABLED_KEY, String.valueOf(dto.getDuckduckgoEnabled()), "DuckDuckGo 免 Key 搜索（零配置兜底）");
+        }
+        if (dto.getSearxngBaseUrl() != null) {
+            saveValue(SEARXNG_BASE_URL_KEY, dto.getSearxngBaseUrl(), "SearXNG 实例地址");
+        }
         return getSettings();
     }
 

mateclaw-server/src/main/java/vip/mate/tool/builtin/WebSearchService.java

@@ -1,16 +1,27 @@
 package vip.mate.tool.builtin;
 
-import cn.hutool.http.HttpUtil;
-import cn.hutool.json.JSONObject;
-import cn.hutool.json.JSONUtil;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Service;
 import vip.mate.system.model.SystemSettingsDTO;
 import vip.mate.system.service.SystemSettingService;
+import vip.mate.tool.search.SearchProvider;
+import vip.mate.tool.search.SearchProviderRegistry;
+import vip.mate.tool.search.SearchProviderRegistry.ResolvedProvider;
+import vip.mate.tool.search.SearchResult;
+
+import java.util.List;
+import java.util.stream.Collectors;
 
 /**
- * 搜索服务：封装 Serper / Tavily 双 provider + fallback 逻辑
+ * 搜索服务：通过 {@link SearchProviderRegistry} 实现 provider chain 路由与 keyless fallback
+ *
+ * <p>调度策略：
+ * <ol>
+ *   <li>用户配置的 primary provider（有 key）</li>
+ *   <li>自动探测其他有 key 的 provider</li>
+ *   <li>Keyless fallback（DuckDuckGo / SearXNG）</li>
+ * </ol>
  *
  * @author MateClaw Team
  */
@@ -20,9 +31,10 @@ import vip.mate.system.service.SystemSettingService;
 public class WebSearchService {
 
     private final SystemSettingService systemSettingService;
+    private final SearchProviderRegistry providerRegistry;
 
     /**
-     * 执行搜索，根据系统设置动态选择 provider
+     * 执行搜索，根据系统设置动态选择 provider（含 keyless fallback）
      */
     public String search(String query) {
         SystemSettingsDTO config = systemSettingService.getSearchSettings();
@@ -31,94 +43,60 @@ public class WebSearchService {
             return "搜索功能已关闭，请在系统设置中启用。";
         }
 
-        String primaryProvider = config.getSearchProvider();
+        // 通过 provider registry 解析最佳 provider
-        if (primaryProvider == null || primaryProvider.isBlank()) {
+        ResolvedProvider resolved = providerRegistry.resolve(config);
-            primaryProvider = "serper";
+        log.info("搜索 provider 解析: {}", resolved != null
-        }
+                ? resolved.provider().id() + " (source=" + resolved.source() + ")"
+                : "无可用 provider");
 
-        // 尝试主 provider
+        if (resolved != null) {
-        String result = doSearch(query, primaryProvider, config);
+            String result = tryProvider(resolved.provider(), query, config);
-        if (result != null) {
-            return result;
-        }
-
-        // 主 provider 失败，尝试 fallback
-        if (Boolean.TRUE.equals(config.getSearchFallbackEnabled())) {
-            String fallbackProvider = "serper".equals(primaryProvider) ? "tavily" : "serper";
-            log.info("主搜索提供商 {} 调用失败，回退到 {}", primaryProvider, fallbackProvider);
-            result = doSearch(query, fallbackProvider, config);
             if (result != null) {
+                log.info("搜索成功 (provider={}, source={})", resolved.provider().id(), resolved.source());
                 return result;
             }
         }
 
-        return "搜索失败：所有搜索提供商均不可用，请在系统设置中检查 API Key 配置。";
+        // 首选 provider 失败或不可用，遍历 fallback chain
+        if (Boolean.TRUE.equals(config.getSearchFallbackEnabled()) || resolved == null) {
+            for (SearchProvider p : providerRegistry.allSorted()) {
+                if (resolved != null && p.id().equals(resolved.provider().id())) continue;
+                if (!p.isAvailable(config)) continue;
+
+                String result = tryProvider(p, query, config);
+                if (result != null) {
+                    log.info("搜索 fallback 成功 (provider={})", p.id());
+                    return result;
+                }
+            }
+        }
+
+        return "搜索暂时不可用。建议在系统设置中配置 Serper 或 Tavily API Key 以获得更好的搜索体验。";
+    }
+
+    private String tryProvider(SearchProvider provider, String query, SystemSettingsDTO config) {
+        try {
+            List<SearchResult> results = provider.search(query, config);
+            if (results == null || results.isEmpty()) {
+                log.debug("Provider {} 返回空结果", provider.id());
+                return null;
+            }
+            return formatResults(results, provider.id());
+        } catch (Exception e) {
+            log.warn("Provider {} 搜索失败: {}", provider.id(), e.getMessage());
+            return null;
+        }
     }
 
     /**
-     * 调用指定 provider 执行搜索，失败返回 null
+     * 将结构化搜索结果格式化为 Markdown（供 LLM 消费）
      */
-    private String doSearch(String query, String provider, SystemSettingsDTO config) {
+    private String formatResults(List<SearchResult> results, String providerId) {
-        try {
+        StringBuilder sb = new StringBuilder();
-            return switch (provider) {
+        sb.append("Search results (via ").append(providerId).append("):\n\n");
-                case "serper" -> searchWithSerper(query, config);
+        for (int i = 0; i < results.size(); i++) {
-                case "tavily" -> searchWithTavily(query, config);
+            sb.append(i + 1).append(". ").append(results.get(i).toMarkdown()).append("\n");
-                default -> {
-                    log.warn("未知的搜索提供商: {}", provider);
-                    yield null;
-                }
-            };
-        } catch (Exception e) {
-            log.error("搜索提供商 {} 调用异常: {}", provider, e.getMessage(), e);
-            return null;
         }
-    }
+        return sb.toString();
-
-    private String searchWithSerper(String query, SystemSettingsDTO config) {
-        String apiKey = config.getSerperApiKey();
-        if (apiKey == null || apiKey.isBlank()) {
-            log.warn("Serper API Key 未配置");
-            return null;
-        }
-        String baseUrl = config.getSerperBaseUrl();
-        if (baseUrl == null || baseUrl.isBlank()) {
-            baseUrl = "https://google.serper.dev/search";
-        }
-
-        String body = JSONUtil.toJsonStr(new JSONObject().set("q", query).set("num", 5));
-        String result = HttpUtil.createPost(baseUrl)
-                .header("X-API-KEY", apiKey)
-                .header("Content-Type", "application/json")
-                .body(body)
-                .timeout(15000)
-                .execute()
-                .body();
-        log.debug("Serper search result for '{}': {}", query, result);
-        return result;
-    }
-
-    private String searchWithTavily(String query, SystemSettingsDTO config) {
-        String apiKey = config.getTavilyApiKey();
-        if (apiKey == null || apiKey.isBlank()) {
-            log.warn("Tavily API Key 未配置");
-            return null;
-        }
-        String baseUrl = config.getTavilyBaseUrl();
-        if (baseUrl == null || baseUrl.isBlank()) {
-            baseUrl = "https://api.tavily.com/search";
-        }
-
-        String body = JSONUtil.toJsonStr(new JSONObject()
-                .set("query", query)
-                .set("max_results", 5)
-                .set("api_key", apiKey));
-        String result = HttpUtil.createPost(baseUrl)
-                .header("Content-Type", "application/json")
-                .body(body)
-                .timeout(15000)
-                .execute()
-                .body();
-        log.debug("Tavily search result for '{}': {}", query, result);
-        return result;
     }
 }

mateclaw-server/src/main/java/vip/mate/tool/search/DuckDuckGoSearchProvider.java

@@ -0,0 +1,176 @@
+package vip.mate.tool.search;
+
+import cn.hutool.http.HttpUtil;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Component;
+import vip.mate.system.model.SystemSettingsDTO;
+
+import java.net.URI;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * DuckDuckGo 搜索提供商 — 无需 API Key（keyless fallback）
+ *
+ * <p>通过 DuckDuckGo HTML 端点实现免 key 搜索。
+ * 作为零配置兜底方案，结果质量不如 Serper/Tavily 但"总比没有强"。
+ *
+ * @author MateClaw Team
+ */
+@Slf4j
+@Component
+public class DuckDuckGoSearchProvider implements SearchProvider {
+
+    private static final String SEARCH_URL = "https://html.duckduckgo.com/html/";
+
+    // 匹配 DuckDuckGo HTML 搜索结果
+    private static final Pattern RESULT_PATTERN = Pattern.compile(
+            "<a[^>]+class=\"result__a\"[^>]+href=\"([^\"]+)\"[^>]*>(.+?)</a>",
+            Pattern.DOTALL);
+    private static final Pattern SNIPPET_PATTERN = Pattern.compile(
+            "<a[^>]+class=\"result__snippet\"[^>]*>(.+?)</a>",
+            Pattern.DOTALL);
+    private static final Pattern RESULT_BLOCK_PATTERN = Pattern.compile(
+            "<div[^>]+class=\"result results_links[^\"]*\"[^>]*>(.*?)</div>\\s*(?=<div[^>]+class=\"result |$)",
+            Pattern.DOTALL);
+
+    @Override
+    public String id() {
+        return "duckduckgo";
+    }
+
+    @Override
+    public String label() {
+        return "DuckDuckGo";
+    }
+
+    @Override
+    public boolean requiresCredential() {
+        return false;
+    }
+
+    @Override
+    public int autoDetectOrder() {
+        return 100;
+    }
+
+    @Override
+    public boolean isAvailable(SystemSettingsDTO config) {
+        // 通过 duckduckgoEnabled 控制，默认启用
+        return !Boolean.FALSE.equals(config.getDuckduckgoEnabled());
+    }
+
+    @Override
+    public List<SearchResult> search(String query, SystemSettingsDTO config) {
+        String encoded = URLEncoder.encode(query, StandardCharsets.UTF_8);
+
+        // DuckDuckGo 在部分网络环境下可能出现 SSLHandshakeException，加一次重试
+        String response = null;
+        int maxAttempts = 2;
+        for (int attempt = 1; attempt <= maxAttempts; attempt++) {
+            try {
+                response = HttpUtil.createPost(SEARCH_URL)
+                        .header("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36")
+                        .header("Content-Type", "application/x-www-form-urlencoded")
+                        .header("Accept", "text/html")
+                        .header("Accept-Language", "en-US,en;q=0.9,zh-CN;q=0.8")
+                        .body("q=" + encoded)
+                        .timeout(15000)
+                        .execute()
+                        .body();
+                break; // 成功则跳出
+            } catch (Exception e) {
+                log.warn("DuckDuckGo 请求失败 (attempt {}/{}): {}", attempt, maxAttempts, e.getMessage());
+                if (attempt == maxAttempts) {
+                    throw e; // 最后一次仍失败则抛出，由 WebSearchService 捕获
+                }
+                try {
+                    Thread.sleep(1000); // 短暂等待后重试
+                } catch (InterruptedException ie) {
+                    Thread.currentThread().interrupt();
+                    throw new RuntimeException("DuckDuckGo 搜索被中断", ie);
+                }
+            }
+        }
+
+        log.debug("DuckDuckGo search completed for '{}', response length: {}", query,
+                response != null ? response.length() : 0);
+        return parseHtmlResults(response);
+    }
+
+    private List<SearchResult> parseHtmlResults(String html) {
+        List<SearchResult> results = new ArrayList<>();
+        if (html == null || html.isBlank()) return results;
+
+        // 提取每个结果块
+        Matcher titleMatcher = RESULT_PATTERN.matcher(html);
+        Matcher snippetMatcher = SNIPPET_PATTERN.matcher(html);
+
+        int count = 0;
+        while (titleMatcher.find() && count < 5) {
+            String rawUrl = titleMatcher.group(1);
+            String rawTitle = titleMatcher.group(2);
+
+            String url = decodeUrl(rawUrl);
+            String title = stripHtml(rawTitle);
+
+            String snippet = "";
+            if (snippetMatcher.find()) {
+                snippet = stripHtml(snippetMatcher.group(1));
+            }
+
+            if (title.isBlank() && snippet.isBlank()) continue;
+
+            results.add(SearchResult.builder()
+                    .title(title)
+                    .url(url)
+                    .snippet(snippet)
+                    .source(extractDomain(url))
+                    .providerId(id())
+                    .build());
+            count++;
+        }
+
+        log.debug("DuckDuckGo 解析到 {} 条结果", results.size());
+        return results;
+    }
+
+    /**
+     * DuckDuckGo 返回的 URL 经过跳转编码 (//duckduckgo.com/l/?uddg=...)，需要解码
+     */
+    private String decodeUrl(String rawUrl) {
+        if (rawUrl == null) return "";
+        // DuckDuckGo 使用 redirect URL
+        if (rawUrl.contains("uddg=")) {
+            try {
+                String encoded = rawUrl.substring(rawUrl.indexOf("uddg=") + 5);
+                int ampIndex = encoded.indexOf('&');
+                if (ampIndex > 0) encoded = encoded.substring(0, ampIndex);
+                return java.net.URLDecoder.decode(encoded, StandardCharsets.UTF_8);
+            } catch (Exception e) {
+                log.debug("URL 解码失败: {}", rawUrl);
+            }
+        }
+        return rawUrl;
+    }
+
+    private String stripHtml(String html) {
+        if (html == null) return "";
+        return html.replaceAll("<[^>]+>", "").replaceAll("&amp;", "&")
+                .replaceAll("&lt;", "<").replaceAll("&gt;", ">")
+                .replaceAll("&quot;", "\"").replaceAll("&#39;", "'")
+                .trim();
+    }
+
+    private String extractDomain(String url) {
+        try {
+            return URI.create(url).getHost();
+        } catch (Exception e) {
+            return null;
+        }
+    }
+}

mateclaw-server/src/main/java/vip/mate/tool/search/SearXNGSearchProvider.java

@@ -0,0 +1,111 @@
+package vip.mate.tool.search;
+
+import cn.hutool.http.HttpUtil;
+import cn.hutool.json.JSONArray;
+import cn.hutool.json.JSONObject;
+import cn.hutool.json.JSONUtil;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Component;
+import vip.mate.system.model.SystemSettingsDTO;
+
+import java.net.URI;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * SearXNG 搜索提供商 — 无需 API Key，但需要 base URL（自部署实例）
+ *
+ * <p>SearXNG 是开源的元搜索引擎，可自部署。Docker 部署 MateClaw 时自动包含 SearXNG 服务，
+ * 默认 base URL 为 {@code http://searxng:8080}。
+ *
+ * @author MateClaw Team
+ */
+@Slf4j
+@Component
+public class SearXNGSearchProvider implements SearchProvider {
+
+    @Override
+    public String id() {
+        return "searxng";
+    }
+
+    @Override
+    public String label() {
+        return "SearXNG";
+    }
+
+    @Override
+    public boolean requiresCredential() {
+        return false;
+    }
+
+    @Override
+    public int autoDetectOrder() {
+        // SearXNG 聚合多引擎，结果质量高于 DuckDuckGo（order=100），应优先
+        return 50;
+    }
+
+    @Override
+    public boolean isAvailable(SystemSettingsDTO config) {
+        String baseUrl = config.getSearxngBaseUrl();
+        return baseUrl != null && !baseUrl.isBlank();
+    }
+
+    @Override
+    public List<SearchResult> search(String query, SystemSettingsDTO config) {
+        String baseUrl = config.getSearxngBaseUrl();
+        if (baseUrl.endsWith("/")) {
+            baseUrl = baseUrl.substring(0, baseUrl.length() - 1);
+        }
+
+        String encoded = URLEncoder.encode(query, StandardCharsets.UTF_8);
+        String url = baseUrl + "/search?q=" + encoded + "&format=json&categories=general&language=auto";
+
+        String response = HttpUtil.createGet(url)
+                .header("Accept", "application/json")
+                .timeout(15000)
+                .execute()
+                .body();
+
+        log.debug("SearXNG result for '{}': length={}", query, response != null ? response.length() : 0);
+        return parseResponse(response);
+    }
+
+    private List<SearchResult> parseResponse(String response) {
+        List<SearchResult> results = new ArrayList<>();
+        if (response == null || response.isBlank()) return results;
+
+        try {
+            JSONObject json = JSONUtil.parseObj(response);
+            JSONArray items = json.getJSONArray("results");
+            if (items == null) return results;
+
+            int limit = Math.min(items.size(), 5);
+            for (int i = 0; i < limit; i++) {
+                JSONObject item = items.getJSONObject(i);
+                String itemUrl = item.getStr("url");
+                results.add(SearchResult.builder()
+                        .title(item.getStr("title"))
+                        .url(itemUrl)
+                        .snippet(item.getStr("content"))
+                        .source(extractDomain(itemUrl))
+                        .date(item.getStr("publishedDate"))
+                        .providerId(id())
+                        .build());
+            }
+        } catch (Exception e) {
+            log.warn("SearXNG 结果解析失败: {}", e.getMessage());
+        }
+        return results;
+    }
+
+    private String extractDomain(String url) {
+        try {
+            return URI.create(url).getHost();
+        } catch (Exception e) {
+            return null;
+        }
+    }
+}

mateclaw-server/src/main/java/vip/mate/tool/search/SearchProvider.java

@@ -0,0 +1,45 @@
+package vip.mate.tool.search;
+
+import vip.mate.system.model.SystemSettingsDTO;
+
+import java.util.List;
+
+/**
+ * 搜索提供商接口 — 所有搜索 provider（含 keyless）统一实现此接口
+ *
+ * @author MateClaw Team
+ */
+public interface SearchProvider {
+
+    /** 提供商唯一 ID，如 "serper"、"tavily"、"duckduckgo"、"searxng" */
+    String id();
+
+    /** 显示名称 */
+    String label();
+
+    /** 是否需要 API Key / Credential */
+    boolean requiresCredential();
+
+    /**
+     * 自动探测排序优先级（升序）。
+     * <p>有 key 的 provider 用较大值（300+），keyless 用较小值（100+），
+     * 但实际调度时"有 credential 的 provider"优先于 keyless，
+     * 此字段仅在同类 provider 之间排序。
+     */
+    int autoDetectOrder();
+
+    /**
+     * 判断该 provider 在当前配置下是否可用
+     * （key 已配置 / keyless provider 已启用等）
+     */
+    boolean isAvailable(SystemSettingsDTO config);
+
+    /**
+     * 执行搜索，返回结构化结果列表
+     *
+     * @param query  搜索关键词
+     * @param config 系统配置（包含 key、baseUrl 等）
+     * @return 搜索结果列表；不应返回 null，失败时抛异常
+     */
+    List<SearchResult> search(String query, SystemSettingsDTO config);
+}

mateclaw-server/src/main/java/vip/mate/tool/search/SearchProviderRegistry.java

@@ -0,0 +1,102 @@
+package vip.mate.tool.search;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Component;
+import vip.mate.system.model.SystemSettingsDTO;
+
+import java.util.Comparator;
+import java.util.List;
+import java.util.Map;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+/**
+ * 搜索提供商注册表 — 收集所有 {@link SearchProvider} 实现，提供优先级排序与自动探测
+ *
+ * <p>借鉴 openclaw 的 provider auto-detect 机制：
+ * <ol>
+ *   <li>用户显式配置的 primary provider → 直接使用</li>
+ *   <li>按 autoDetectOrder 遍历，优先选有 credential 的 provider</li>
+ *   <li>如果没有有 credential 的 provider，回退到第一个可用的 keyless provider</li>
+ * </ol>
+ *
+ * @author MateClaw Team
+ */
+@Slf4j
+@Component
+public class SearchProviderRegistry {
+
+    private final List<SearchProvider> sortedProviders;
+    private final Map<String, SearchProvider> providerMap;
+
+    public SearchProviderRegistry(List<SearchProvider> providers) {
+        this.sortedProviders = providers.stream()
+                .sorted(Comparator.comparingInt(SearchProvider::autoDetectOrder))
+                .toList();
+        this.providerMap = providers.stream()
+                .collect(Collectors.toMap(SearchProvider::id, Function.identity()));
+        log.info("注册搜索提供商 {} 个: {}", sortedProviders.size(),
+                sortedProviders.stream().map(p -> p.id() + "(order=" + p.autoDetectOrder() + ")").toList());
+    }
+
+    /** 按 ID 获取指定 provider */
+    public SearchProvider getById(String id) {
+        return providerMap.get(id);
+    }
+
+    /** 获取按 autoDetectOrder 排序的全部 provider 列表 */
+    public List<SearchProvider> allSorted() {
+        return sortedProviders;
+    }
+
+    /**
+     * 根据当前配置，解析应使用的 provider。
+     *
+     * <p>解析策略（借鉴 openclaw resolveWebSearchProviderId）：
+     * <ol>
+     *   <li>如果用户配置了 primary provider 且该 provider 可用 → 选中</li>
+     *   <li>否则按 autoDetectOrder 遍历，跳过 keyless，先找有 credential 的</li>
+     *   <li>如果没找到 → 回退到第一个可用的 keyless provider</li>
+     * </ol>
+     *
+     * @return 选中的 provider，或 null（完全无可用 provider）
+     */
+    public ResolvedProvider resolve(SystemSettingsDTO config) {
+        // 1. 用户显式配置的 primary provider
+        String configuredId = config.getSearchProvider();
+        if (configuredId != null && !configuredId.isBlank()) {
+            SearchProvider configured = providerMap.get(configuredId);
+            if (configured != null && configured.isAvailable(config)) {
+                return new ResolvedProvider(configured, "configured");
+            }
+        }
+
+        // 2. 按优先级遍历，先找有 credential 的
+        SearchProvider keylessFallback = null;
+        for (SearchProvider p : sortedProviders) {
+            if (!p.requiresCredential()) {
+                // 记住第一个可用的 keyless provider
+                if (keylessFallback == null && p.isAvailable(config)) {
+                    keylessFallback = p;
+                }
+                continue;
+            }
+            if (p.isAvailable(config)) {
+                return new ResolvedProvider(p, "auto-detect");
+            }
+        }
+
+        // 3. 回退到 keyless
+        if (keylessFallback != null) {
+            return new ResolvedProvider(keylessFallback, "keyless-fallback");
+        }
+
+        return null;
+    }
+
+    /**
+     * 解析结果
+     */
+    public record ResolvedProvider(SearchProvider provider, String source) {
+    }
+}

mateclaw-server/src/main/java/vip/mate/tool/search/SearchResult.java

@@ -0,0 +1,54 @@
+package vip.mate.tool.search;
+
+import lombok.Builder;
+import lombok.Data;
+
+/**
+ * 统一搜索结果结构 — 所有 provider 返回此格式
+ *
+ * @author MateClaw Team
+ */
+@Data
+@Builder
+public class SearchResult {
+
+    /** 结果标题 */
+    private String title;
+
+    /** 结果链接 */
+    private String url;
+
+    /** 摘要/片段 */
+    private String snippet;
+
+    /** 来源域名 (如 "reuters.com") */
+    private String source;
+
+    /** 发布时间（原始字符串，尽可能保留） */
+    private String date;
+
+    /** 提供该结果的 provider id */
+    private String providerId;
+
+    /**
+     * 格式化为 Markdown 行，用于返回给 LLM
+     */
+    public String toMarkdown() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("**").append(title != null ? title : "Untitled").append("**");
+        if (source != null || date != null) {
+            sb.append(" — ");
+            if (source != null) sb.append(source);
+            if (source != null && date != null) sb.append(" | ");
+            if (date != null) sb.append(date);
+        }
+        sb.append("\n");
+        if (snippet != null && !snippet.isBlank()) {
+            sb.append(snippet).append("\n");
+        }
+        if (url != null && !url.isBlank()) {
+            sb.append("🔗 ").append(url).append("\n");
+        }
+        return sb.toString();
+    }
+}

mateclaw-server/src/main/java/vip/mate/tool/search/SerperSearchProvider.java

@@ -0,0 +1,105 @@
+package vip.mate.tool.search;
+
+import cn.hutool.http.HttpUtil;
+import cn.hutool.json.JSONArray;
+import cn.hutool.json.JSONObject;
+import cn.hutool.json.JSONUtil;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Component;
+import vip.mate.system.model.SystemSettingsDTO;
+
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Serper (Google Search) 搜索提供商 — 需要 API Key
+ *
+ * @author MateClaw Team
+ */
+@Slf4j
+@Component
+public class SerperSearchProvider implements SearchProvider {
+
+    private static final String DEFAULT_BASE_URL = "https://google.serper.dev/search";
+
+    @Override
+    public String id() {
+        return "serper";
+    }
+
+    @Override
+    public String label() {
+        return "Serper (Google)";
+    }
+
+    @Override
+    public boolean requiresCredential() {
+        return true;
+    }
+
+    @Override
+    public int autoDetectOrder() {
+        return 300;
+    }
+
+    @Override
+    public boolean isAvailable(SystemSettingsDTO config) {
+        String key = config.getSerperApiKey();
+        return key != null && !key.isBlank();
+    }
+
+    @Override
+    public List<SearchResult> search(String query, SystemSettingsDTO config) {
+        String apiKey = config.getSerperApiKey();
+        String baseUrl = config.getSerperBaseUrl();
+        if (baseUrl == null || baseUrl.isBlank()) {
+            baseUrl = DEFAULT_BASE_URL;
+        }
+
+        String body = JSONUtil.toJsonStr(new JSONObject().set("q", query).set("num", 5));
+        String response = HttpUtil.createPost(baseUrl)
+                .header("X-API-KEY", apiKey)
+                .header("Content-Type", "application/json")
+                .body(body)
+                .timeout(15000)
+                .execute()
+                .body();
+
+        log.debug("Serper result for '{}': {}", query, response);
+        return parseResponse(response);
+    }
+
+    private List<SearchResult> parseResponse(String response) {
+        List<SearchResult> results = new ArrayList<>();
+        try {
+            JSONObject json = JSONUtil.parseObj(response);
+            JSONArray organic = json.getJSONArray("organic");
+            if (organic == null) return results;
+
+            for (int i = 0; i < organic.size(); i++) {
+                JSONObject item = organic.getJSONObject(i);
+                String url = item.getStr("link");
+                results.add(SearchResult.builder()
+                        .title(item.getStr("title"))
+                        .url(url)
+                        .snippet(item.getStr("snippet"))
+                        .source(extractDomain(url))
+                        .date(item.getStr("date"))
+                        .providerId(id())
+                        .build());
+            }
+        } catch (Exception e) {
+            log.warn("Serper 结果解析失败: {}", e.getMessage());
+        }
+        return results;
+    }
+
+    private String extractDomain(String url) {
+        try {
+            return URI.create(url).getHost();
+        } catch (Exception e) {
+            return null;
+        }
+    }
+}

mateclaw-server/src/main/java/vip/mate/tool/search/TavilySearchProvider.java

@@ -0,0 +1,107 @@
+package vip.mate.tool.search;
+
+import cn.hutool.http.HttpUtil;
+import cn.hutool.json.JSONArray;
+import cn.hutool.json.JSONObject;
+import cn.hutool.json.JSONUtil;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Component;
+import vip.mate.system.model.SystemSettingsDTO;
+
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Tavily 搜索提供商 — 需要 API Key
+ *
+ * @author MateClaw Team
+ */
+@Slf4j
+@Component
+public class TavilySearchProvider implements SearchProvider {
+
+    private static final String DEFAULT_BASE_URL = "https://api.tavily.com/search";
+
+    @Override
+    public String id() {
+        return "tavily";
+    }
+
+    @Override
+    public String label() {
+        return "Tavily";
+    }
+
+    @Override
+    public boolean requiresCredential() {
+        return true;
+    }
+
+    @Override
+    public int autoDetectOrder() {
+        return 400;
+    }
+
+    @Override
+    public boolean isAvailable(SystemSettingsDTO config) {
+        String key = config.getTavilyApiKey();
+        return key != null && !key.isBlank();
+    }
+
+    @Override
+    public List<SearchResult> search(String query, SystemSettingsDTO config) {
+        String apiKey = config.getTavilyApiKey();
+        String baseUrl = config.getTavilyBaseUrl();
+        if (baseUrl == null || baseUrl.isBlank()) {
+            baseUrl = DEFAULT_BASE_URL;
+        }
+
+        String body = JSONUtil.toJsonStr(new JSONObject()
+                .set("query", query)
+                .set("max_results", 5)
+                .set("api_key", apiKey));
+        String response = HttpUtil.createPost(baseUrl)
+                .header("Content-Type", "application/json")
+                .body(body)
+                .timeout(15000)
+                .execute()
+                .body();
+
+        log.debug("Tavily result for '{}': {}", query, response);
+        return parseResponse(response);
+    }
+
+    private List<SearchResult> parseResponse(String response) {
+        List<SearchResult> results = new ArrayList<>();
+        try {
+            JSONObject json = JSONUtil.parseObj(response);
+            JSONArray items = json.getJSONArray("results");
+            if (items == null) return results;
+
+            for (int i = 0; i < items.size(); i++) {
+                JSONObject item = items.getJSONObject(i);
+                String url = item.getStr("url");
+                results.add(SearchResult.builder()
+                        .title(item.getStr("title"))
+                        .url(url)
+                        .snippet(item.getStr("content"))
+                        .source(extractDomain(url))
+                        .date(item.getStr("published_date"))
+                        .providerId(id())
+                        .build());
+            }
+        } catch (Exception e) {
+            log.warn("Tavily 结果解析失败: {}", e.getMessage());
+        }
+        return results;
+    }
+
+    private String extractDomain(String url) {
+        try {
+            return URI.create(url).getHost();
+        } catch (Exception e) {
+            return null;
+        }
+    }
+}

mateclaw-server/src/main/resources/db/data-en.sql

@@ -294,6 +294,14 @@ MERGE INTO mate_system_setting (id, setting_key, setting_value, description, cre
 KEY (id)
 VALUES (1000000011, 'tavilyBaseUrl', 'https://api.tavily.com/search', 'Tavily base URL', NOW(), NOW());
 
+MERGE INTO mate_system_setting (id, setting_key, setting_value, description, create_time, update_time)
+KEY (id)
+VALUES (1000000012, 'duckduckgoEnabled', 'true', 'DuckDuckGo keyless search fallback (zero-config)', NOW(), NOW());
+
+MERGE INTO mate_system_setting (id, setting_key, setting_value, description, create_time, update_time)
+KEY (id)
+VALUES (1000000013, 'searxngBaseUrl', '', 'SearXNG instance base URL (auto-configured in Docker)', NOW(), NOW());
+
 -- Built-in tool: Date & Time
 MERGE INTO mate_tool (id, name, display_name, description, tool_type, bean_name, icon, enabled, builtin, create_time, update_time, deleted)
 KEY (id)

mateclaw-server/src/main/resources/db/data-mysql-en.sql

@@ -296,6 +296,14 @@ INSERT INTO mate_system_setting (id, setting_key, setting_value, description, cr
 VALUES (1000000011, 'tavilyBaseUrl', 'https://api.tavily.com/search', 'Tavily base URL', NOW(), NOW())
 ON DUPLICATE KEY UPDATE setting_key=VALUES(setting_key), setting_value=VALUES(setting_value), description=VALUES(description), update_time=VALUES(update_time);
 
+INSERT INTO mate_system_setting (id, setting_key, setting_value, description, create_time, update_time)
+VALUES (1000000012, 'duckduckgoEnabled', 'true', 'DuckDuckGo keyless search fallback (zero-config)', NOW(), NOW())
+ON DUPLICATE KEY UPDATE setting_key=VALUES(setting_key), setting_value=VALUES(setting_value), description=VALUES(description), update_time=VALUES(update_time);
+
+INSERT INTO mate_system_setting (id, setting_key, setting_value, description, create_time, update_time)
+VALUES (1000000013, 'searxngBaseUrl', '', 'SearXNG instance base URL (auto-configured in Docker)', NOW(), NOW())
+ON DUPLICATE KEY UPDATE setting_key=VALUES(setting_key), setting_value=VALUES(setting_value), description=VALUES(description), update_time=VALUES(update_time);
+
 -- Built-in tool: Date & Time
 INSERT INTO mate_tool (id, name, display_name, description, tool_type, bean_name, icon, enabled, builtin, create_time, update_time, deleted)
 VALUES (1000000001, 'DateTimeTool', 'Date & Time', 'Get current date and time information', 'builtin', 'dateTimeTool', '🕐', TRUE, TRUE, NOW(), NOW(), 0)

mateclaw-server/src/main/resources/db/data-mysql-zh.sql

@@ -296,6 +296,14 @@ INSERT INTO mate_system_setting (id, setting_key, setting_value, description, cr
 VALUES (1000000011, 'tavilyBaseUrl', 'https://api.tavily.com/search', 'Tavily 接口地址', NOW(), NOW())
 ON DUPLICATE KEY UPDATE setting_key=VALUES(setting_key), setting_value=VALUES(setting_value), description=VALUES(description), update_time=VALUES(update_time);
 
+INSERT INTO mate_system_setting (id, setting_key, setting_value, description, create_time, update_time)
+VALUES (1000000012, 'duckduckgoEnabled', 'true', 'DuckDuckGo 免 Key 搜索兜底（零配置可用）', NOW(), NOW())
+ON DUPLICATE KEY UPDATE setting_key=VALUES(setting_key), setting_value=VALUES(setting_value), description=VALUES(description), update_time=VALUES(update_time);
+
+INSERT INTO mate_system_setting (id, setting_key, setting_value, description, create_time, update_time)
+VALUES (1000000013, 'searxngBaseUrl', '', 'SearXNG 实例地址（Docker 部署时自动配置）', NOW(), NOW())
+ON DUPLICATE KEY UPDATE setting_key=VALUES(setting_key), setting_value=VALUES(setting_value), description=VALUES(description), update_time=VALUES(update_time);
+
 -- 内置工具：日期时间
 INSERT INTO mate_tool (id, name, display_name, description, tool_type, bean_name, icon, enabled, builtin, create_time, update_time, deleted)
 VALUES (1000000001, 'DateTimeTool', '日期时间', '获取当前日期和时间信息', 'builtin', 'dateTimeTool', '🕐', TRUE, TRUE, NOW(), NOW(), 0)

mateclaw-server/src/main/resources/db/data-zh.sql

@@ -300,6 +300,14 @@ MERGE INTO mate_system_setting (id, setting_key, setting_value, description, cre
 KEY (id)
 VALUES (1000000011, 'tavilyBaseUrl', 'https://api.tavily.com/search', 'Tavily 接口地址', NOW(), NOW());
 
+MERGE INTO mate_system_setting (id, setting_key, setting_value, description, create_time, update_time)
+KEY (id)
+VALUES (1000000012, 'duckduckgoEnabled', 'true', 'DuckDuckGo 免 Key 搜索兜底（零配置可用）', NOW(), NOW());
+
+MERGE INTO mate_system_setting (id, setting_key, setting_value, description, create_time, update_time)
+KEY (id)
+VALUES (1000000013, 'searxngBaseUrl', '', 'SearXNG 实例地址（Docker 部署时自动配置）', NOW(), NOW());
+
 -- 内置工具：日期时间
 MERGE INTO mate_tool (id, name, display_name, description, tool_type, bean_name, icon, enabled, builtin, create_time, update_time, deleted)
 KEY (id)

mateclaw-ui/src/i18n/locales/en-US.ts

@@ -330,6 +330,8 @@ export default {
       serperBaseUrl: 'Serper Base URL',
       tavilyApiKey: 'Tavily API Key',
       tavilyBaseUrl: 'Tavily Base URL',
+      duckduckgoEnabled: 'DuckDuckGo (Keyless)',
+      searxngBaseUrl: 'SearXNG Base URL',
     },
     hints: {
       provider: 'Current implementation applies DashScope model options at runtime.',
@@ -343,6 +345,8 @@ export default {
       serperBaseUrl: 'Usually no need to change unless using a custom proxy.',
       tavilyApiKey: 'API key for Tavily search, get it from tavily.com.',
       tavilyBaseUrl: 'Usually no need to change unless using a custom proxy.',
+      duckduckgoEnabled: 'Free keyless search fallback. No API key required. Enabled by default as a zero-config fallback.',
+      searxngBaseUrl: 'Self-hosted SearXNG instance URL. Auto-configured when deploying via Docker.',
     },
     searchTitle: 'Search Service',
     searchDesc: 'Configure the built-in search tool provider and API credentials',

mateclaw-ui/src/i18n/locales/zh-CN.ts

@@ -330,6 +330,8 @@ export default {
       serperBaseUrl: 'Serper 接口地址',
       tavilyApiKey: 'Tavily API Key',
       tavilyBaseUrl: 'Tavily 接口地址',
+      duckduckgoEnabled: 'DuckDuckGo（免 Key）',
+      searxngBaseUrl: 'SearXNG 地址',
     },
     hints: {
       provider: '当前版本会把 DashScope 模型参数真实应用到 Agent 调用链路。',
@@ -343,6 +345,8 @@ export default {
       serperBaseUrl: '通常无需修改，除非使用自定义代理地址。',
       tavilyApiKey: '用于 Tavily 搜索服务，从 tavily.com 获取。',
       tavilyBaseUrl: '通常无需修改，除非使用自定义代理地址。',
+      duckduckgoEnabled: '免费搜索兜底，无需 API Key。默认开启，作为零配置下的搜索降级方案。',
+      searxngBaseUrl: '自部署 SearXNG 实例地址。Docker 部署时自动配置。',
     },
     searchTitle: '搜索服务',
     searchDesc: '配置内置搜索工具的提供商与 API 凭证',

mateclaw-ui/src/types/index.ts

@@ -499,6 +499,9 @@ export interface SystemSettings {
   tavilyBaseUrl: string
   serperApiKeyMasked?: string
   tavilyApiKeyMasked?: string
+  // Keyless 搜索 provider
+  duckduckgoEnabled: boolean
+  searxngBaseUrl: string
 }
 
 export interface ProviderModelInfo {

mateclaw-ui/src/views/Settings/System/index.vue

@@ -159,6 +159,36 @@
           />
         </div>
       </div>
+
+      <!-- Keyless Provider 配置 -->
+      <div class="setting-item">
+        <div class="setting-info">
+          <div class="setting-label">{{ t('settings.fields.duckduckgoEnabled') }}</div>
+          <div class="setting-hint">{{ t('settings.hints.duckduckgoEnabled') }}</div>
+        </div>
+        <div class="setting-control">
+          <label class="toggle-switch">
+            <input v-model="settings.duckduckgoEnabled" type="checkbox" :disabled="!settings.searchEnabled" />
+            <span class="toggle-slider"></span>
+          </label>
+        </div>
+      </div>
+
+      <div class="setting-item setting-item-vertical">
+        <div class="setting-info">
+          <div class="setting-label">{{ t('settings.fields.searxngBaseUrl') }}</div>
+          <div class="setting-hint">{{ t('settings.hints.searxngBaseUrl') }}</div>
+        </div>
+        <div class="setting-control-full">
+          <input
+            v-model="settings.searxngBaseUrl"
+            type="text"
+            class="form-input"
+            placeholder="http://searxng:8080"
+            :disabled="!settings.searchEnabled"
+          />
+        </div>
+      </div>
     </div>
 
     <div class="save-bar">
@@ -193,6 +223,8 @@ const settings = reactive<SystemSettings>({
   searchFallbackEnabled: false,
   serperBaseUrl: 'https://google.serper.dev/search',
   tavilyBaseUrl: 'https://api.tavily.com/search',
+  duckduckgoEnabled: true,
+  searxngBaseUrl: '',
 })
 
 onMounted(async () => {