初始化提交

mcp/web-search/internal/balancer/balancer.go

@@ -0,0 +1,264 @@
+package balancer
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/config"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// KeySearcher 按密钥执行搜索的接口。
+// 与 SearchProvider 解耦，方便测试时注入 mock。
+type KeySearcher interface {
+	Search(ctx context.Context, apiKey string, req *models.SearchRequest) (*models.SearchResult, error)
+	HealthCheck(ctx context.Context) error
+	Name() models.ProviderKind
+}
+
+// LoadBalancer 负载均衡器（goroutine-safe）。
+type LoadBalancer struct {
+	pools      map[models.ProviderKind]*KeyPool
+	searchers  map[models.ProviderKind]KeySearcher
+	disabled   map[models.ProviderKind]bool // 运行时动态禁用
+	retryCount int
+	mu         sync.RWMutex
+}
+
+func NewLoadBalancer(cfg *config.BalancerConfig) *LoadBalancer {
+	return &LoadBalancer{
+		pools:      make(map[models.ProviderKind]*KeyPool),
+		searchers:  make(map[models.ProviderKind]KeySearcher),
+		disabled:   make(map[models.ProviderKind]bool),
+		retryCount: cfg.RetryCount,
+	}
+}
+
+// AddProvider 注册 provider 及其密钥池。
+func (lb *LoadBalancer) AddProvider(
+	provider models.ProviderKind,
+	keys []string,
+	weight int,
+	searcher KeySearcher,
+) {
+	lb.mu.Lock()
+	defer lb.mu.Unlock()
+
+	cbThreshold := 5
+	cbCooldown := 30 * time.Second
+	lb.pools[provider] = NewKeyPool(provider, keys, weight, cbThreshold, cbCooldown)
+	lb.searchers[provider] = searcher
+	// 添加时默认启用
+	delete(lb.disabled, provider)
+}
+
+// RemoveProvider 移除 provider 及其密钥池。
+func (lb *LoadBalancer) RemoveProvider(provider models.ProviderKind) {
+	lb.mu.Lock()
+	defer lb.mu.Unlock()
+	delete(lb.pools, provider)
+	delete(lb.searchers, provider)
+	delete(lb.disabled, provider)
+}
+
+// EnableProvider 启用 provider。
+func (lb *LoadBalancer) EnableProvider(provider models.ProviderKind) {
+	lb.mu.Lock()
+	defer lb.mu.Unlock()
+	delete(lb.disabled, provider)
+}
+
+// DisableProvider 禁用 provider（搜索时跳过，不删除配置）。
+func (lb *LoadBalancer) DisableProvider(provider models.ProviderKind) {
+	lb.mu.Lock()
+	defer lb.mu.Unlock()
+	lb.disabled[provider] = true
+}
+
+// IsProviderEnabled 检查 provider 是否启用。
+func (lb *LoadBalancer) IsProviderEnabled(provider models.ProviderKind) bool {
+	lb.mu.RLock()
+	defer lb.mu.RUnlock()
+	return !lb.disabled[provider]
+}
+
+// SetRetryCount 更新重试次数。
+func (lb *LoadBalancer) SetRetryCount(n int) {
+	lb.mu.Lock()
+	defer lb.mu.Unlock()
+	lb.retryCount = n
+}
+
+// HasProvider 检查 provider 是否已注册。
+func (lb *LoadBalancer) HasProvider(provider models.ProviderKind) bool {
+	lb.mu.RLock()
+	defer lb.mu.RUnlock()
+	_, ok := lb.pools[provider]
+	return ok
+}
+
+// Search 执行搜索（自动选密钥、跨 provider 重试）。
+func (lb *LoadBalancer) Search(ctx context.Context, req *models.SearchRequest) (*models.SearchResult, error) {
+	providers := lb.resolveProviders(req.Providers)
+
+	var lastErr error
+	for attempt := 0; attempt <= lb.getRetryCount(); attempt++ {
+		for _, prov := range providers {
+			pool, ok := lb.pools[prov]
+			if !ok {
+				continue
+			}
+			ks := pool.Select()
+			if ks == nil {
+				continue
+			}
+			searcher := lb.searchers[prov]
+			if searcher == nil {
+				continue
+			}
+
+			start := time.Now()
+			result, err := searcher.Search(ctx, ks.Key, req)
+			duration := time.Since(start)
+
+			if err != nil {
+				ks.RecordFailure()
+				lastErr = err
+				continue
+			}
+			ks.RecordSuccess(duration)
+			result.Provider = prov
+			return result, nil
+		}
+	}
+
+	if lastErr != nil {
+		return nil, fmt.Errorf("balancer: all providers exhausted: %w", lastErr)
+	}
+	return nil, fmt.Errorf("balancer: no available provider or key for query: %s", req.Query)
+}
+
+// SearchAll 并发搜索所有启用 provider（用于 Merge 模式）。
+func (lb *LoadBalancer) SearchAll(ctx context.Context, req *models.SearchRequest) []*models.SearchResult {
+	providers := lb.resolveProviders(nil)
+	type result struct {
+		prov models.ProviderKind
+		res  *models.SearchResult
+		err  error
+	}
+
+	ch := make(chan result, len(providers))
+	for _, prov := range providers {
+		p := prov
+		go func() {
+			pool, ok := lb.pools[p]
+			if !ok {
+				ch <- result{prov: p, err: fmt.Errorf("no pool")}
+				return
+			}
+			ks := pool.Select()
+			if ks == nil {
+				ch <- result{prov: p, err: fmt.Errorf("no available key")}
+				return
+			}
+			searcher := lb.searchers[p]
+			if searcher == nil {
+				ch <- result{prov: p, err: fmt.Errorf("no searcher")}
+				return
+			}
+			start := time.Now()
+			res, err := searcher.Search(ctx, ks.Key, req)
+			duration := time.Since(start)
+			if err != nil {
+				ks.RecordFailure()
+				ch <- result{prov: p, err: err}
+				return
+			}
+			ks.RecordSuccess(duration)
+			res.Provider = p
+			ch <- result{prov: p, res: res}
+		}()
+	}
+
+	var results []*models.SearchResult
+	for range providers {
+		r := <-ch
+		if r.res != nil {
+			results = append(results, r.res)
+		}
+	}
+	return results
+}
+
+// ActiveKeyCount 返回每个 provider 的活跃密钥数。
+// ActiveKeyCount 返回每个 provider 的活跃密钥数。
+// ActiveKeyCount 返回每个 provider 的活跃密钥数。
+func (lb *LoadBalancer) ActiveKeyCount() map[models.ProviderKind]int {
+	lb.mu.RLock()
+	defer lb.mu.RUnlock()
+	out := make(map[models.ProviderKind]int)
+	for p, pool := range lb.pools {
+		if lb.disabled[p] {
+			continue
+		}
+		out[p] = pool.ActiveCount()
+	}
+	return out
+}
+
+// Providers 返回所有已注册的 provider 名称（无论启用与否）。
+func (lb *LoadBalancer) Providers() []models.ProviderKind {
+	lb.mu.RLock()
+	defer lb.mu.RUnlock()
+	out := make([]models.ProviderKind, 0, len(lb.pools))
+	for p := range lb.pools {
+		out = append(out, p)
+	}
+	return out
+}
+
+// HealthCheck 对指定 provider 执行健康检查（委托给 KeySearcher）。
+func (lb *LoadBalancer) HealthCheck(ctx context.Context, provider models.ProviderKind) error {
+	lb.mu.RLock()
+	searcher, ok := lb.searchers[provider]
+	lb.mu.RUnlock()
+	if !ok {
+		return fmt.Errorf("healthcheck: provider not found: %s", provider)
+	}
+	return searcher.HealthCheck(ctx)
+}
+
+func (lb *LoadBalancer) getRetryCount() int {
+	lb.mu.RLock()
+	defer lb.mu.RUnlock()
+	return lb.retryCount
+}
+
+// resolveProviders 按用户偏好和可用性确定 provider 顺序（跳过已禁用的）。
+func (lb *LoadBalancer) resolveProviders(preferred []string) []models.ProviderKind {
+	lb.mu.RLock()
+	defer lb.mu.RUnlock()
+
+	if len(preferred) == 0 {
+		out := make([]models.ProviderKind, 0, len(lb.pools))
+		for p := range lb.pools {
+			if !lb.disabled[p] {
+				out = append(out, p)
+			}
+		}
+		return out
+	}
+
+	out := make([]models.ProviderKind, 0, len(preferred))
+	seen := make(map[models.ProviderKind]bool)
+	for _, name := range preferred {
+		p := models.ProviderKind(name)
+		if _, ok := lb.pools[p]; ok && !seen[p] && !lb.disabled[p] {
+			out = append(out, p)
+			seen[p] = true
+		}
+	}
+	return out
+}

mcp/web-search/internal/balancer/balancer_test.go

@@ -0,0 +1,90 @@
+package balancer
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/config"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+type mockSearcher struct {
+	name   models.ProviderKind
+	failOn int // 第几次调用失败（0 = 永不）
+	calls  int
+}
+
+func (m *mockSearcher) Search(ctx context.Context, apiKey string, req *models.SearchRequest) (*models.SearchResult, error) {
+	m.calls++
+	if m.failOn > 0 && m.calls >= m.failOn {
+		return nil, errors.New("mock failure")
+	}
+	return &models.SearchResult{Provider: m.name, Query: req.Query, Results: []models.ResultItem{{Title: "mock"}}}, nil
+}
+func (m *mockSearcher) HealthCheck(ctx context.Context) error { return nil }
+func (m *mockSearcher) Name() models.ProviderKind             { return m.name }
+
+func TestLoadBalancer_Search_Basic(t *testing.T) {
+	lb := NewLoadBalancer(&config.BalancerConfig{RetryCount: 1})
+	lb.AddProvider(models.ProviderTavily, []string{"key1"}, 1, &mockSearcher{name: models.ProviderTavily})
+
+	result, err := lb.Search(context.Background(), &models.SearchRequest{Query: "test"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if result.Provider != models.ProviderTavily {
+		t.Errorf("expected tavily, got %s", result.Provider)
+	}
+}
+
+func TestLoadBalancer_Search_FallbackProvider(t *testing.T) {
+	lb := NewLoadBalancer(&config.BalancerConfig{RetryCount: 1})
+	lb.AddProvider(models.ProviderTavily, []string{"key1"}, 1, &mockSearcher{name: models.ProviderTavily, failOn: 1})
+	lb.AddProvider(models.ProviderBrave, []string{"key1"}, 1, &mockSearcher{name: models.ProviderBrave})
+
+	result, err := lb.Search(context.Background(), &models.SearchRequest{Query: "test"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if string(result.Provider) != "brave" {
+		t.Errorf("expected fallback to brave, got %s", result.Provider)
+	}
+}
+
+func TestLoadBalancer_Search_AllExhausted(t *testing.T) {
+	lb := NewLoadBalancer(&config.BalancerConfig{RetryCount: 0})
+	lb.AddProvider(models.ProviderTavily, []string{"key1"}, 1, &mockSearcher{name: models.ProviderTavily, failOn: 1})
+
+	_, err := lb.Search(context.Background(), &models.SearchRequest{Query: "test"})
+	if err == nil {
+		t.Fatal("expected error when all keys exhausted")
+	}
+}
+
+func TestLoadBalancer_Search_PreferredProviders(t *testing.T) {
+	lb := NewLoadBalancer(&config.BalancerConfig{RetryCount: 0})
+	lb.AddProvider(models.ProviderTavily, []string{"key1"}, 1, &mockSearcher{name: models.ProviderTavily})
+	lb.AddProvider(models.ProviderBrave, []string{"key1"}, 1, &mockSearcher{name: models.ProviderBrave})
+
+	result, err := lb.Search(context.Background(), &models.SearchRequest{
+		Query:     "test",
+		Providers: []string{"brave"},
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if result.Provider != models.ProviderBrave {
+		t.Errorf("expected bing (preferred), got %s", result.Provider)
+	}
+}
+
+func TestLoadBalancer_ActiveKeyCount(t *testing.T) {
+	lb := NewLoadBalancer(&config.BalancerConfig{RetryCount: 0})
+	lb.AddProvider(models.ProviderTavily, []string{"key1", "key2"}, 1, &mockSearcher{name: models.ProviderTavily})
+
+	counts := lb.ActiveKeyCount()
+	if counts[models.ProviderTavily] != 2 {
+		t.Errorf("expected 2 active keys, got %d", counts[models.ProviderTavily])
+	}
+}

mcp/web-search/internal/balancer/checker.go

@@ -0,0 +1,117 @@
+package balancer
+
+import (
+	"context"
+	"log/slog"
+	"sync"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/config"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// HealthChecker 定期对已注册 provider 执行健康检查。
+// 连续失败超过阈值时自动禁用 provider，恢复成功后自动启用。
+type HealthChecker struct {
+	lb       *LoadBalancer
+	interval time.Duration
+	timeout  time.Duration
+	threshold int
+
+	mu        sync.Mutex
+	failures  map[models.ProviderKind]int // 连续失败计数
+	done      chan struct{}
+}
+
+// NewHealthChecker 创建健康检查器。cfg 为对应 provider 的健康检查配置。
+func NewHealthChecker(lb *LoadBalancer, cfg config.HealthCheckConf) *HealthChecker {
+	return &HealthChecker{
+		lb:        lb,
+		interval:  cfg.Interval,
+		timeout:   cfg.Timeout,
+		threshold: cfg.FailureThreshold,
+		failures:  make(map[models.ProviderKind]int),
+		done:      make(chan struct{}),
+	}
+}
+
+// Start 在后台 goroutine 中启动健康检查循环。
+// 每隔 interval 时间对所有已注册 provider 执行一次健康检查。
+func (hc *HealthChecker) Start() {
+	if hc.interval <= 0 {
+		return
+	}
+	slog.Info("健康检查已启动", "interval", hc.interval, "timeout", hc.timeout, "failure_threshold", hc.threshold)
+	go hc.loop()
+}
+
+// Stop 停止健康检查循环。
+func (hc *HealthChecker) Stop() {
+	close(hc.done)
+}
+
+func (hc *HealthChecker) loop() {
+	ticker := time.NewTicker(hc.interval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ticker.C:
+			hc.checkAll()
+		case <-hc.done:
+			return
+		}
+	}
+}
+
+func (hc *HealthChecker) checkAll() {
+	// 获取当前所有已注册 provider 的名称
+	// 我们需要从 LoadBalancer 获取提供者列表
+	// 由于 LoadBalancer 没有直接暴露 provider 列表的 API，我们遍历 ActiveKeyCount
+	// 来获取所有已知的 provider
+	for _, prov := range hc.getAllProviders() {
+		hc.checkProvider(prov)
+	}
+}
+
+func (hc *HealthChecker) checkProvider(prov models.ProviderKind) {
+	ctx, cancel := context.WithTimeout(context.Background(), hc.timeout)
+	defer cancel()
+
+	err := hc.lb.HealthCheck(ctx, prov)
+
+	hc.mu.Lock()
+	defer hc.mu.Unlock()
+
+	if err != nil {
+		hc.failures[prov]++
+		fails := hc.failures[prov]
+		slog.Warn("健康检查失败",
+			"provider", prov,
+			"consecutive_failures", fails,
+			"error", err,
+		)
+		if fails >= hc.threshold && hc.lb.IsProviderEnabled(prov) {
+			hc.lb.DisableProvider(prov)
+			slog.Warn("健康检查: provider 已自动禁用",
+				"provider", prov,
+				"failures", fails,
+			)
+		}
+	} else {
+		// 恢复成功
+		if hc.failures[prov] > 0 {
+			slog.Info("健康检查恢复", "provider", prov)
+		}
+		hc.failures[prov] = 0
+		if !hc.lb.IsProviderEnabled(prov) {
+			hc.lb.EnableProvider(prov)
+			slog.Info("健康检查: provider 已自动启用", "provider", prov)
+		}
+	}
+}
+
+// getAllProviders 返回当前所有已注册的 provider 名称（包括已禁用的）。
+func (hc *HealthChecker) getAllProviders() []models.ProviderKind {
+	return hc.lb.Providers()
+}

mcp/web-search/internal/balancer/circuitbreaker.go

@@ -0,0 +1,103 @@
+// Package balancer 实现密钥池管理和负载均衡。
+package balancer
+
+import (
+	"sync"
+	"time"
+)
+
+// State 熔断器状态。
+type State int
+
+const (
+	StateClosed   State = iota // 正常
+	StateOpen                  // 熔断
+	StateHalfOpen              // 半开（探测）
+)
+
+func (s State) String() string {
+	switch s {
+	case StateClosed:
+		return "closed"
+	case StateOpen:
+		return "open"
+	case StateHalfOpen:
+		return "half-open"
+	default:
+		return "unknown"
+	}
+}
+
+// CircuitBreaker 熔断器。
+type CircuitBreaker struct {
+	mu              sync.Mutex
+	state           State
+	failures        int
+	threshold       int
+	cooldown        time.Duration
+	lastFailureTime time.Time
+}
+
+func NewCircuitBreaker(threshold int, cooldown time.Duration) *CircuitBreaker {
+	return &CircuitBreaker{
+		state:     StateClosed,
+		threshold: threshold,
+		cooldown:  cooldown,
+	}
+}
+
+// Allow 判断是否允许请求通过。
+func (cb *CircuitBreaker) Allow() bool {
+	cb.mu.Lock()
+	defer cb.mu.Unlock()
+
+	switch cb.state {
+	case StateClosed:
+		return true
+	case StateOpen:
+		if time.Since(cb.lastFailureTime) > cb.cooldown {
+			cb.state = StateHalfOpen
+			return true
+		}
+		return false
+	case StateHalfOpen:
+		return true
+	default:
+		return true
+	}
+}
+
+// Success 记录成功。
+func (cb *CircuitBreaker) Success() {
+	cb.mu.Lock()
+	defer cb.mu.Unlock()
+	cb.failures = 0
+	if cb.state == StateHalfOpen {
+		cb.state = StateClosed
+	}
+}
+
+// Failure 记录失败。
+func (cb *CircuitBreaker) Failure() {
+	cb.mu.Lock()
+	defer cb.mu.Unlock()
+	cb.failures++
+	cb.lastFailureTime = time.Now()
+	if cb.state == StateHalfOpen || cb.failures >= cb.threshold {
+		cb.state = StateOpen
+	}
+}
+
+// State 返回当前状态（goroutine-safe 快照）。
+func (cb *CircuitBreaker) State() State {
+	cb.mu.Lock()
+	defer cb.mu.Unlock()
+	return cb.state
+}
+
+// Failures 返回连续失败次数。
+func (cb *CircuitBreaker) Failures() int {
+	cb.mu.Lock()
+	defer cb.mu.Unlock()
+	return cb.failures
+}

mcp/web-search/internal/balancer/keypool.go

@@ -0,0 +1,169 @@
+package balancer
+
+import (
+	"math"
+	"sync"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// KeyStatus 密钥状态。
+type KeyStatus int
+
+const (
+	KeyActive   KeyStatus = iota // 正常
+	KeyCooldown                  // 冷却中（熔断后）
+	KeyDead                      // 死亡（多次失败不再恢复）
+)
+
+// KeyState 单个密钥状态。
+type KeyState struct {
+	Provider models.ProviderKind
+	Key      string
+	Weight   int
+
+	mu           sync.Mutex
+	status       KeyStatus
+	latencyEWMA  time.Duration // 指数加权滑动平均延迟
+	successCount int64
+	failCount    int64
+	cb           *CircuitBreaker
+}
+
+func newKeyState(provider models.ProviderKind, key string, weight int, cbThreshold int, cbCooldown time.Duration) *KeyState {
+	return &KeyState{
+		Provider: provider,
+		Key:      key,
+		Weight:   weight,
+		status:   KeyActive,
+		cb:       NewCircuitBreaker(cbThreshold, cbCooldown),
+	}
+}
+
+// Allow 检查是否允许使用此密钥。
+func (ks *KeyState) Allow() bool {
+	ks.mu.Lock()
+	defer ks.mu.Unlock()
+	if ks.status != KeyActive {
+		return false
+	}
+	return ks.cb.Allow()
+}
+
+// RecordSuccess 记录成功调用，更新 EWMA 延迟。
+func (ks *KeyState) RecordSuccess(latency time.Duration) {
+	ks.mu.Lock()
+	defer ks.mu.Unlock()
+	ks.successCount++
+	ks.cb.Success()
+	// EWMA 更新：α = 0.3
+	alpha := 0.3
+	if ks.latencyEWMA == 0 {
+		ks.latencyEWMA = latency
+	} else {
+		ks.latencyEWMA = time.Duration(
+			(1-alpha)*float64(ks.latencyEWMA) + alpha*float64(latency),
+		)
+	}
+	ks.status = KeyActive
+}
+
+// RecordFailure 记录失败调用。
+func (ks *KeyState) RecordFailure() {
+	ks.mu.Lock()
+	defer ks.mu.Unlock()
+	ks.failCount++
+	ks.cb.Failure()
+	if ks.cb.State() == StateOpen {
+		ks.status = KeyCooldown
+	}
+}
+
+// CombinedScore 计算综合分数（越高优先选用）。
+// 综合 = 基础权重 × 延迟惩罚 × 可靠性因子
+func (ks *KeyState) CombinedScore() float64 {
+	ks.mu.Lock()
+	defer ks.mu.Unlock()
+
+	if ks.status != KeyActive {
+		return 0
+	}
+	if ks.cb.State() != StateClosed {
+		return 0
+	}
+
+	base := float64(ks.Weight)
+	latencyPenalty := 1.0
+	if ks.latencyEWMA > 0 {
+		latencyPenalty = 1.0 / (1.0 + ks.latencyEWMA.Seconds())
+	}
+	reliability := 1.0
+	total := ks.successCount + ks.failCount
+	if total > 0 && ks.failCount > 0 {
+		reliability = 1.0 - float64(ks.failCount)/float64(total)
+	}
+	return base * latencyPenalty * math.Max(0.1, reliability)
+}
+
+// KeyPool 管理一个 provider 下的多密钥。
+type KeyPool struct {
+	provider    models.ProviderKind
+	keys        []*KeyState
+	mu          sync.RWMutex
+	cbThreshold int
+	cbCooldown  time.Duration
+}
+
+func NewKeyPool(provider models.ProviderKind, keys []string, weight int, cbThreshold int, cbCooldown time.Duration) *KeyPool {
+	kp := &KeyPool{
+		provider:    provider,
+		keys:        make([]*KeyState, 0, len(keys)),
+		cbThreshold: cbThreshold,
+		cbCooldown:  cbCooldown,
+	}
+	for _, k := range keys {
+		kp.keys = append(kp.keys, newKeyState(provider, k, weight, cbThreshold, cbCooldown))
+	}
+	return kp
+}
+
+// Select 按综合分数选最佳密钥。
+func (kp *KeyPool) Select() *KeyState {
+	kp.mu.RLock()
+	defer kp.mu.RUnlock()
+
+	var best *KeyState
+	var bestScore float64
+	for _, ks := range kp.keys {
+		if !ks.Allow() {
+			continue
+		}
+		score := ks.CombinedScore()
+		if score > bestScore {
+			bestScore = score
+			best = ks
+		}
+	}
+	return best
+}
+
+// ActiveCount 返回活跃密钥数。
+func (kp *KeyPool) ActiveCount() int {
+	kp.mu.RLock()
+	defer kp.mu.RUnlock()
+	count := 0
+	for _, ks := range kp.keys {
+		if ks.status == KeyActive {
+			count++
+		}
+	}
+	return count
+}
+
+// TotalCount 返回密钥总数。
+func (kp *KeyPool) TotalCount() int {
+	kp.mu.RLock()
+	defer kp.mu.RUnlock()
+	return len(kp.keys)
+}

mcp/web-search/internal/balancer/keypool_test.go

@@ -0,0 +1,123 @@
+package balancer
+
+import (
+	"testing"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+func TestKeyPool_Select_Basic(t *testing.T) {
+	kp := NewKeyPool(models.ProviderTavily, []string{"key1", "key2"}, 1, 5, 30*time.Second)
+	ks := kp.Select()
+	if ks == nil {
+		t.Fatal("expected to select a key")
+	}
+	if ks.Key != "key1" && ks.Key != "key2" {
+		t.Errorf("unexpected key: %s", ks.Key)
+	}
+}
+
+func TestKeyPool_Select_SkipsDead(t *testing.T) {
+	kp := NewKeyPool(models.ProviderTavily, []string{"key1", "key2"}, 1, 2, 1*time.Hour)
+	ks1 := kp.Select()
+
+	// Fail twice to trigger circuit breaker
+	ks1.RecordFailure()
+	ks1.RecordFailure()
+
+	selected := kp.Select()
+	if selected == nil {
+		t.Fatal("expected fallback to second key")
+	}
+	if selected.Key == ks1.Key {
+		t.Error("should not select the failed key")
+	}
+}
+
+func TestKeyState_CombinedScore(t *testing.T) {
+	ks := newKeyState(models.ProviderTavily, "test-key", 2, 5, 30*time.Second)
+	score := ks.CombinedScore()
+	if score <= 0 {
+		t.Errorf("expected positive score, got %f", score)
+	}
+
+	// After recording a slow latency, score should drop
+	ks.RecordSuccess(2 * time.Second)
+	slowScore := ks.CombinedScore()
+	if slowScore >= score {
+		t.Error("expected slow latency to reduce score")
+	}
+}
+
+func TestCircuitBreaker_OpenAndRecover(t *testing.T) {
+	cb := NewCircuitBreaker(3, 50*time.Millisecond)
+
+	// Should be closed initially
+	if !cb.Allow() {
+		t.Error("expected allow initially")
+	}
+
+	// Fail 3 times to open
+	cb.Failure()
+	cb.Failure()
+	cb.Failure()
+	if cb.Allow() {
+		t.Error("expected circuit open after 3 failures")
+	}
+
+	// Wait for cooldown
+	time.Sleep(60 * time.Millisecond)
+	if !cb.Allow() {
+		t.Error("expected allow after cooldown")
+	}
+
+	// Half-open: success should close
+	cb.Success()
+	if cb.State() != StateClosed {
+		t.Error("expected circuit closed after half-open success")
+	}
+}
+
+func TestCircuitBreaker_HalfOpenFailure(t *testing.T) {
+	cb := NewCircuitBreaker(3, 50*time.Millisecond)
+
+	cb.Failure()
+	cb.Failure()
+	cb.Failure()
+	if cb.Allow() {
+		t.Error("expected open")
+	}
+
+	time.Sleep(60 * time.Millisecond)
+	if !cb.Allow() {
+		t.Error("expected half-open allow")
+	}
+
+	// Half-open: failure should re-open immediately
+	cb.Failure()
+	if cb.State() != StateOpen {
+		t.Error("expected open after half-open failure")
+	}
+}
+
+func TestKeyPool_ActiveCount(t *testing.T) {
+	kp := NewKeyPool(models.ProviderTavily, []string{"key1", "key2", "key3"}, 1, 3, 30*time.Second)
+	if kp.TotalCount() != 3 {
+		t.Errorf("expected 3 total, got %d", kp.TotalCount())
+	}
+	if kp.ActiveCount() != 3 {
+		t.Errorf("expected 3 active, got %d", kp.ActiveCount())
+	}
+}
+
+func TestKeyPool_AllKeysDead(t *testing.T) {
+	kp := NewKeyPool(models.ProviderTavily, []string{"key1"}, 1, 1, 1*time.Hour)
+	ks := kp.Select()
+	ks.RecordFailure()
+
+	selected := kp.Select()
+	if selected != nil {
+		t.Error("expected nil when all keys dead")
+	}
+}

mcp/web-search/internal/cache/cache.go

@@ -0,0 +1,222 @@
+// Package cache 提供搜索缓存（两级：内存 LRU + 可选 Redis）。
+package cache
+
+import (
+	"context"
+	"crypto/sha256"
+	"encoding/json"
+	"fmt"
+	"sync"
+	"time"
+
+	lru "github.com/hashicorp/golang-lru/v2"
+	"github.com/redis/go-redis/v9"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/config"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// entry 缓存条目。
+type entry struct {
+	result    *models.SearchResult
+	expiresAt time.Time
+}
+
+// Manager 两级缓存管理器。
+// L1: 内存 LRU（本地毫秒级，单进程共享）
+// L2: Redis（跨实例共享，可按开关关闭）
+type Manager struct {
+	enabled bool
+	ttl     time.Duration
+	lru     *lru.Cache[string, *entry]
+	rdb     *redis.Client
+	redisDB int
+	mu      sync.RWMutex
+	l1Hits  int64
+	l2Hits  int64
+	misses  int64
+}
+
+// New 创建缓存管理器。若 Redis 启用则初始化 L2 连接。
+func New(cfg config.CacheConfig) (*Manager, error) {
+	if !cfg.Enabled {
+		return &Manager{enabled: false}, nil
+	}
+
+	c, err := lru.New[string, *entry](cfg.MaxItems)
+	if err != nil {
+		return nil, fmt.Errorf("cache: create lru: %w", err)
+	}
+
+	m := &Manager{
+		enabled: true,
+		ttl:     cfg.TTL,
+		lru:     c,
+	}
+
+	// 初始化 Redis 连接（仅 enabled 时）
+	if cfg.Redis.Enabled {
+		m.rdb = redis.NewClient(&redis.Options{
+			Addr:     cfg.Redis.Addr,
+			Password: cfg.Redis.Password,
+			DB:       cfg.Redis.DB,
+		})
+		m.redisDB = cfg.Redis.DB
+		// 探测 Redis 连通性
+		if err := m.rdb.Ping(context.Background()).Err(); err != nil {
+			return nil, fmt.Errorf("cache: redis ping failed: %w", err)
+		}
+	}
+
+	return m, nil
+}
+
+// cacheKey 生成缓存键。格式：bowen:cache:{provider}:{hash[:8]}:{max_results}
+func cacheKey(req *models.SearchRequest, provider models.ProviderKind) string {
+	h := sha256.Sum256([]byte(fmt.Sprintf("%s:%s:%d", provider, req.Query, req.MaxResults)))
+	return fmt.Sprintf("bowen:cache:%x:%d", h[:8], req.MaxResults)
+}
+
+// Get 获取缓存结果。
+// 查询顺序：L1 (LRU) → L2 (Redis) → nil
+// 若 L2 命中，自动升温到 L1。
+func (m *Manager) Get(req *models.SearchRequest, provider models.ProviderKind) *models.SearchResult {
+	if !m.enabled {
+		return nil
+	}
+	key := cacheKey(req, provider)
+
+	// L1: 内存 LRU
+	if result := m.getL1(key); result != nil {
+		m.mu.Lock()
+		m.l1Hits++
+		m.mu.Unlock()
+		return result
+	}
+
+	// L2: Redis（如启用）
+	if m.rdb != nil {
+		if result := m.getL2(key); result != nil {
+			// 升温到 L1
+			m.setL1(key, result)
+			m.mu.Lock()
+			m.l2Hits++
+			m.mu.Unlock()
+			return result
+		}
+	}
+
+	m.mu.Lock()
+	m.misses++
+	m.mu.Unlock()
+	return nil
+}
+
+func (m *Manager) getL1(key string) *models.SearchResult {
+	m.mu.RLock()
+	e, ok := m.lru.Get(key)
+	m.mu.RUnlock()
+	if !ok {
+		return nil
+	}
+	if time.Now().After(e.expiresAt) {
+		m.mu.Lock()
+		m.lru.Remove(key)
+		m.mu.Unlock()
+		return nil
+	}
+	result := *e.result
+	result.Cached = true
+	return &result
+}
+
+func (m *Manager) getL2(key string) *models.SearchResult {
+	data, err := m.rdb.Get(context.Background(), key).Bytes()
+	if err != nil {
+		return nil
+	}
+	var result models.SearchResult
+	if err := json.Unmarshal(data, &result); err != nil {
+		return nil
+	}
+	result.Cached = true
+	return &result
+}
+
+// Set 写入缓存（L1 + L2，若 Redis 启用则同步写 L2）。
+func (m *Manager) Set(req *models.SearchRequest, provider models.ProviderKind, result *models.SearchResult) {
+	if !m.enabled {
+		return
+	}
+	key := cacheKey(req, provider)
+
+	// 写 L1
+	m.setL1(key, result)
+
+	// 写 L2（异步 fire-and-forget，不阻塞）
+	if m.rdb != nil {
+		go func() {
+			data, err := json.Marshal(result)
+			if err != nil {
+				return
+			}
+			m.rdb.Set(context.Background(), key, data, m.ttl)
+		}()
+	}
+}
+
+func (m *Manager) setL1(key string, result *models.SearchResult) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	r := *result
+	m.lru.Add(key, &entry{
+		result:    &r,
+		expiresAt: time.Now().Add(m.ttl),
+	})
+}
+
+// Stats 缓存统计（L1 命中、L2 命中、L1+L2 总未命中）。
+func (m *Manager) Stats() (l1Hits, l2Hits, misses int64) {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+	return m.l1Hits, m.l2Hits, m.misses
+}
+
+// HitRate 综合缓存命中率（L1+L2 命中 / 总请求）。
+func (m *Manager) HitRate() float64 {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+	total := m.l1Hits + m.l2Hits + m.misses
+	if total == 0 {
+		return 0
+	}
+	return float64(m.l1Hits+m.l2Hits) / float64(total)
+}
+
+// SetTTL 运行时更新 TTL（仅影响后续写入的条目）。
+func (m *Manager) SetTTL(d time.Duration) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.ttl = d
+}
+
+// Clear 清空缓存。
+func (m *Manager) Clear() {
+	if !m.enabled {
+		return
+	}
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.lru.Purge()
+	m.l1Hits = 0
+	m.l2Hits = 0
+	m.misses = 0
+}
+
+// Close 关闭 Redis 连接。
+func (m *Manager) Close() error {
+	if m.rdb != nil {
+		return m.rdb.Close()
+	}
+	return nil
+}

mcp/web-search/internal/cache/cache_test.go

@@ -0,0 +1,122 @@
+package cache
+
+import (
+	"testing"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/config"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+func TestCache_SetAndGet(t *testing.T) {
+	m, err := New(config.CacheConfig{
+		Enabled:  true,
+		TTL:      5 * time.Minute,
+		MaxItems: 100,
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	req := &models.SearchRequest{Query: "test", MaxResults: 5}
+	result := &models.SearchResult{Query: "test", TotalCount: 1}
+
+	m.Set(req, models.ProviderTavily, result)
+	got := m.Get(req, models.ProviderTavily)
+	if got == nil {
+		t.Fatal("expected cached result")
+	}
+	if !got.Cached {
+		t.Error("expected cached=true")
+	}
+}
+
+func TestCache_Miss(t *testing.T) {
+	m, err := New(config.CacheConfig{
+		Enabled:  true,
+		TTL:      5 * time.Minute,
+		MaxItems: 100,
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	got := m.Get(&models.SearchRequest{Query: "nosuch"}, models.ProviderTavily)
+	if got != nil {
+		t.Fatal("expected nil for cache miss")
+	}
+}
+
+func TestCache_Disabled(t *testing.T) {
+	m, err := New(config.CacheConfig{Enabled: false})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	m.Set(&models.SearchRequest{Query: "test"}, models.ProviderTavily, &models.SearchResult{})
+	got := m.Get(&models.SearchRequest{Query: "test"}, models.ProviderTavily)
+	if got != nil {
+		t.Fatal("expected nil when cache disabled")
+	}
+}
+
+func TestCache_Expired(t *testing.T) {
+	m, err := New(config.CacheConfig{
+		Enabled:  true,
+		TTL:      -1 * time.Second, // 立即过期
+		MaxItems: 100,
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	m.Set(&models.SearchRequest{Query: "test"}, models.ProviderTavily, &models.SearchResult{})
+	got := m.Get(&models.SearchRequest{Query: "test"}, models.ProviderTavily)
+	if got != nil {
+		t.Fatal("expected nil for expired entry")
+	}
+}
+
+func TestCache_Stats(t *testing.T) {
+	m, err := New(config.CacheConfig{
+		Enabled:  true,
+		TTL:      5 * time.Minute,
+		MaxItems: 100,
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	// Miss then hit
+	m.Get(&models.SearchRequest{Query: "miss"}, models.ProviderTavily)
+	m.Set(&models.SearchRequest{Query: "hit"}, models.ProviderTavily, &models.SearchResult{})
+	m.Get(&models.SearchRequest{Query: "hit"}, models.ProviderTavily)
+
+	l1Hits, l2Hits, misses := m.Stats()
+	if l1Hits != 1 {
+		t.Errorf("expected 1 L1 hit, got %d", l1Hits)
+	}
+	if l2Hits != 0 {
+		t.Errorf("expected 0 L2 hits, got %d", l2Hits)
+	}
+	if misses != 1 {
+		t.Errorf("expected 1 miss, got %d", misses)
+	}
+}
+
+func TestCache_ProviderIsolation(t *testing.T) {
+	m, err := New(config.CacheConfig{
+		Enabled:  true,
+		TTL:      5 * time.Minute,
+		MaxItems: 100,
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	req := &models.SearchRequest{Query: "test", MaxResults: 5}
+	m.Set(req, models.ProviderTavily, &models.SearchResult{Query: "test"})
+
+	// Same query, different provider should miss
+	got := m.Get(req, models.ProviderBrave)
+	if got != nil {
+		t.Fatal("expected miss for different provider")
+	}
+}

mcp/web-search/internal/config/config.go

@@ -0,0 +1,179 @@
+// Package config 管理博闻配置。
+package config
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Config 顶层配置。
+type Config struct {
+	Server    ServerConfig    `yaml:"server"`
+	Providers ProvidersConfig `yaml:"providers"`
+	Balancer  BalancerConfig  `yaml:"balancer"`
+	Cache     CacheConfig     `yaml:"cache"`
+	Metrics   MetricsConfig   `yaml:"metrics"`
+}
+
+// ServerConfig 服务端配置。
+type ServerConfig struct {
+	Port         int           `yaml:"port"`
+	ReadTimeout  time.Duration `yaml:"read_timeout"`
+	WriteTimeout time.Duration `yaml:"write_timeout"`
+}
+
+// ProvidersConfig 聚合所有搜索提供商配置。
+type ProvidersConfig struct {
+	Tavily ProviderConfig `yaml:"tavily"`
+	Brave  ProviderConfig `yaml:"brave"`
+}
+
+// ProviderConfig 单个搜索提供商配置。
+type ProviderConfig struct {
+	Enabled     bool            `yaml:"enabled"`
+	Timeout     time.Duration   `yaml:"timeout"`
+	MaxResults  int             `yaml:"max_results"`
+	HealthCheck HealthCheckConf `yaml:"health_check"`
+	// APIKeys 从环境变量注入，不在 YAML 中
+	APIKeys []string `yaml:"-"`
+}
+
+// HealthCheckConf 健康检查配置。
+type HealthCheckConf struct {
+	Interval         time.Duration `yaml:"interval"`
+	Timeout          time.Duration `yaml:"timeout"`
+	FailureThreshold int           `yaml:"failure_threshold"`
+}
+
+// BalancerConfig 负载均衡配置。
+type BalancerConfig struct {
+	Strategy       string            `yaml:"strategy"`
+	RetryCount     int               `yaml:"retry_count"`
+	CircuitBreaker CircuitBreakerCfg `yaml:"circuit_breaker"`
+}
+
+// CircuitBreakerCfg 熔断器配置。
+type CircuitBreakerCfg struct {
+	Enabled          bool          `yaml:"enabled"`
+	FailureThreshold int           `yaml:"failure_threshold"`
+	Cooldown         time.Duration `yaml:"cooldown"`
+}
+
+// CacheConfig 缓存配置。
+type CacheConfig struct {
+	Enabled  bool          `yaml:"enabled"`
+	TTL      time.Duration `yaml:"ttl"`
+	MaxItems int           `yaml:"max_items"`
+	Redis    RedisConfig   `yaml:"redis"`
+}
+
+// RedisConfig Redis 缓存配置（二级缓存层，可开关）。
+type RedisConfig struct {
+	Enabled  bool   `yaml:"enabled"`
+	Addr     string `yaml:"addr"`
+	Password string `yaml:"password"`
+	DB       int    `yaml:"db"`
+}
+
+// MetricsConfig 监控指标配置。
+type MetricsConfig struct {
+	Enabled bool   `yaml:"enabled"`
+	Port    int    `yaml:"port"`
+	Path    string `yaml:"path"`
+}
+
+// envVarKeys 定义各 provider 的 API Key 环境变量名。
+var envVarKeys = map[string]string{
+	"tavily": "TAVILY_API_KEYS",
+	"brave":  "BRAVE_API_KEYS",
+}
+
+// Load 加载配置，API Keys 从环境变量读取。
+// configPath 为可选 YAML 配置文件路径。
+func Load(configPath string) (*Config, error) {
+	cfg := &Config{}
+	setDefaults(cfg)
+
+	// 从 YAML 文件加载（如存在）
+	if configPath != "" {
+		if err := loadFromFile(configPath, cfg); err != nil {
+			return nil, err
+		}
+	}
+
+	// 从环境变量加载 API Keys
+	cfg.Providers.Tavily.APIKeys = parseEnvKeys(envVarKeys["tavily"])
+	cfg.Providers.Brave.APIKeys = parseEnvKeys(envVarKeys["brave"])
+
+	// 从环境变量加载 Redis 配置
+	if env := os.Getenv("MCP_WEB_SEARCH_REDIS_ENABLED"); env != "" {
+		cfg.Cache.Redis.Enabled, _ = strconv.ParseBool(env)
+	}
+	if env := os.Getenv("MCP_WEB_SEARCH_REDIS_ADDR"); env != "" {
+		cfg.Cache.Redis.Addr = env
+	}
+	if env := os.Getenv("MCP_WEB_SEARCH_REDIS_PASSWORD"); env != "" {
+		cfg.Cache.Redis.Password = env
+	}
+	if env := os.Getenv("MCP_WEB_SEARCH_REDIS_DB"); env != "" {
+		if db, err := strconv.Atoi(env); err == nil {
+			cfg.Cache.Redis.DB = db
+		}
+	}
+
+	return cfg, nil
+}
+
+func setDefaults(cfg *Config) {
+	cfg.Server.Port = 8080
+	cfg.Server.ReadTimeout = 30 * time.Second
+	cfg.Server.WriteTimeout = 30 * time.Second
+	// Provider 默认启用（可通过 YAML 中 enabled: false 关闭）
+	cfg.Providers.Tavily.Enabled = true
+	cfg.Providers.Tavily.Timeout = 10 * time.Second
+	cfg.Providers.Tavily.MaxResults = 10
+	cfg.Providers.Brave.Enabled = true
+	cfg.Providers.Brave.Timeout = 10 * time.Second
+	cfg.Providers.Brave.MaxResults = 10
+	cfg.Balancer.Strategy = "weighted_round_robin"
+	cfg.Balancer.RetryCount = 2
+	cfg.Balancer.CircuitBreaker.Enabled = true
+	cfg.Balancer.CircuitBreaker.FailureThreshold = 5
+	cfg.Balancer.CircuitBreaker.Cooldown = 30 * time.Second
+	cfg.Cache.Enabled = true
+	cfg.Cache.TTL = 5 * time.Minute
+	cfg.Cache.MaxItems = 1000
+	cfg.Cache.Redis.Enabled = false
+	cfg.Cache.Redis.Addr = "127.0.0.1:6379"
+	cfg.Cache.Redis.Password = ""
+	cfg.Cache.Redis.DB = 0
+	cfg.Metrics.Enabled = true
+	cfg.Metrics.Port = 9090
+	cfg.Metrics.Path = "/metrics"
+}
+
+func loadFromFile(path string, cfg *Config) error {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return fmt.Errorf("read config: %w", err)
+	}
+	return yamlUnmarshal(data, cfg)
+}
+
+func parseEnvKeys(envName string) []string {
+	val := os.Getenv(envName)
+	if val == "" {
+		return nil
+	}
+	parts := strings.Split(val, ",")
+	keys := make([]string, 0, len(parts))
+	for _, p := range parts {
+		if trimmed := strings.TrimSpace(p); trimmed != "" {
+			keys = append(keys, trimmed)
+		}
+	}
+	return keys
+}

mcp/web-search/internal/config/reloader.go

@@ -0,0 +1,109 @@
+package config
+
+import (
+	"log/slog"
+	"sync"
+	"time"
+
+	"github.com/fsnotify/fsnotify"
+)
+
+// Reloader 配置文件热重载器。
+// 监听 YAML 文件变更，通过 onChange 回调通知调用方。
+type Reloader struct {
+	path     string
+	cfg      *Config
+	watcher  *fsnotify.Watcher
+	onChange func(old, new *Config) error
+	mu       sync.Mutex
+	debounce *time.Timer
+	done     chan struct{}
+}
+
+// NewReloader 创建并启动配置热重载。
+// onChange 在配置变更时被调用，接收 old/new 两份配置。
+func NewReloader(path string, cfg *Config, onChange func(old, new *Config) error) (*Reloader, error) {
+	w, err := fsnotify.NewWatcher()
+	if err != nil {
+		return nil, err
+	}
+	if err := w.Add(path); err != nil {
+		w.Close()
+		return nil, err
+	}
+
+	r := &Reloader{
+		path:     path,
+		cfg:      cfg,
+		watcher:  w,
+		onChange: onChange,
+		debounce: time.NewTimer(0),
+		done:     make(chan struct{}),
+	}
+
+	// 停止初始化的空 timer
+	if !r.debounce.Stop() {
+		<-r.debounce.C
+	}
+
+	go r.loop()
+	slog.Info("配置热重载已启动", "path", path)
+	return r, nil
+}
+
+func (r *Reloader) loop() {
+	for {
+		select {
+		case event := <-r.watcher.Events:
+			if event.Op&(fsnotify.Write|fsnotify.Create|fsnotify.Rename) == 0 {
+				continue
+			}
+			slog.Debug("配置文件变更", "event", event.Name)
+			r.debounce.Reset(500 * time.Millisecond)
+
+		case <-r.debounce.C:
+			r.reload()
+
+		case err := <-r.watcher.Errors:
+			slog.Error("配置热重载监听异常", "error", err)
+
+		case <-r.done:
+			return
+		}
+	}
+}
+
+func (r *Reloader) reload() {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	old := r.cfg
+	// 只重新加载 YAML 部分（API Keys 仍由环境变量管理）
+	updated := *old // 浅拷贝
+	if err := loadFromFile(r.path, &updated); err != nil {
+		slog.Error("配置热重载读取失败", "error", err)
+		return
+	}
+
+	// 保留环境变量注入的值
+	updated.Providers.Tavily.APIKeys = old.Providers.Tavily.APIKeys
+	updated.Providers.Brave.APIKeys = old.Providers.Brave.APIKeys
+	updated.Cache.Redis.Enabled = old.Cache.Redis.Enabled
+	updated.Cache.Redis.Addr = old.Cache.Redis.Addr
+	updated.Cache.Redis.Password = old.Cache.Redis.Password
+	updated.Cache.Redis.DB = old.Cache.Redis.DB
+
+	if err := r.onChange(r.cfg, &updated); err != nil {
+		slog.Error("配置热重载应用失败", "error", err)
+		return
+	}
+
+	r.cfg = &updated
+	slog.Info("配置已热重载")
+}
+
+// Stop 停止配置热重载。
+func (r *Reloader) Stop() {
+	close(r.done)
+	r.watcher.Close()
+}

mcp/web-search/internal/config/yaml.go

@@ -0,0 +1,7 @@
+package config
+
+import "gopkg.in/yaml.v3"
+
+func yamlUnmarshal(data []byte, cfg *Config) error {
+	return yaml.Unmarshal(data, cfg)
+}

mcp/web-search/internal/logger/logger.go

@@ -0,0 +1,136 @@
+// Package logger 提供结构化日志配置。
+package logger
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"log/slog"
+	"os"
+	"strings"
+	"sync"
+)
+
+// Config 日志配置。
+type Config struct {
+	Level     slog.Level
+	AddSource bool
+	JSON      bool // true = JSONHandler，false = 彩色 TextHandler
+}
+
+// New 创建配置好的 Logger。
+// 开发环境（JSON=false）输出彩色终端文本，生产环境输出 JSON 供采集。
+func New(cfg Config) *slog.Logger {
+	var h slog.Handler
+	opts := &slog.HandlerOptions{
+		Level:     cfg.Level,
+		AddSource: cfg.AddSource,
+	}
+	if cfg.JSON {
+		h = slog.NewJSONHandler(os.Stdout, opts)
+	} else {
+		h = newColorHandler(os.Stdout, opts)
+	}
+	return slog.New(h)
+}
+
+// ANSI 颜色代码
+const (
+	colorReset  = "\033[0m"
+	colorRed    = "\033[31m"
+	colorGreen  = "\033[32m"
+	colorYellow = "\033[33m"
+	colorBlue   = "\033[34m"
+	colorPurple = "\033[35m"
+	colorCyan   = "\033[36m"
+	colorGray   = "\033[37m"
+)
+
+// levelColor 日志级别 → ANSI 颜色映射
+var levelColor = map[slog.Level]string{
+	slog.LevelDebug: colorGray,
+	slog.LevelInfo:  colorGreen,
+	slog.LevelWarn:  colorYellow,
+	slog.LevelError: colorRed,
+}
+
+// levelLabel 日志级别 → 短标签映射
+var levelLabel = map[slog.Level]string{
+	slog.LevelDebug: "DEBUG",
+	slog.LevelInfo:  "INFO",
+	slog.LevelWarn:  "WARN",
+	slog.LevelError: "ERROR",
+}
+
+// colorHandler 带颜色的 slog.Handler 包装。
+type colorHandler struct {
+	inner  slog.Handler
+	mu     sync.Mutex
+	writer io.Writer
+}
+
+func newColorHandler(w io.Writer, opts *slog.HandlerOptions) *colorHandler {
+	return &colorHandler{
+		inner:  slog.NewTextHandler(w, opts),
+		writer: w,
+	}
+}
+
+func (h *colorHandler) Enabled(ctx context.Context, level slog.Level) bool {
+	return h.inner.Enabled(ctx, level)
+}
+
+func (h *colorHandler) Handle(ctx context.Context, r slog.Record) error {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+
+	// 时间（使用 -07:00 让 Go 自动填充时区偏移）
+	timeStr := r.Time.Format("2006-01-02T15:04:05.000-07:00")
+
+	// Level 带颜色
+	lvl := r.Level
+	color := levelColor[lvl]
+	label := levelLabel[lvl]
+
+	// 消息
+	msg := r.Message
+
+	// 组装属性
+	var attrs []string
+	r.Attrs(func(a slog.Attr) bool {
+		attrs = append(attrs, fmt.Sprintf("%s=%v", a.Key, a.Value.Any()))
+		return true
+	})
+
+	// 输出格式：[时间] Level颜色(LEVEL) 消息  attr1=val1 attr2=val2
+	var buf strings.Builder
+	buf.WriteString(timeStr)
+	buf.WriteString(" ")
+	buf.WriteString(color)
+	buf.WriteString(fmt.Sprintf("%-5s", label))
+	buf.WriteString(colorReset)
+	buf.WriteString(" ")
+	buf.WriteString(msg)
+	for _, a := range attrs {
+		buf.WriteString(" ")
+		buf.WriteString(a)
+	}
+	buf.WriteString("\n")
+
+	_, err := fmt.Fprint(h.writer, buf.String())
+	return err
+}
+
+func (h *colorHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
+	return &colorHandler{
+		inner:  h.inner.WithAttrs(attrs),
+		writer: h.writer,
+	}
+}
+
+func (h *colorHandler) WithGroup(name string) slog.Handler {
+	return &colorHandler{
+		inner:  h.inner.WithGroup(name),
+		writer: h.writer,
+	}
+}

mcp/web-search/internal/mcp/admin.go

@@ -0,0 +1,116 @@
+package mcp
+
+import (
+	"encoding/json"
+	"log/slog"
+	"net/http"
+	"strings"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// registerAdminRoutes 注册管理端点到 mux。
+func (h *Handler) registerAdminRoutes(mux *http.ServeMux) {
+	mux.HandleFunc("/admin/provider/", h.handleProviderAdmin)
+	mux.HandleFunc("/admin/cache/clear", h.handleCacheClear)
+	mux.HandleFunc("/admin/keys", h.handleKeys)
+}
+
+// handleProviderAdmin 管理 provider 启用/禁用。
+// PUT /admin/provider/{name}/enable
+// PUT /admin/provider/{name}/disable
+func (h *Handler) handleProviderAdmin(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPut {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	// 解析路径：/admin/provider/{name}/{action}
+	parts := strings.Split(strings.TrimPrefix(r.URL.Path, "/admin/provider/"), "/")
+	if len(parts) != 2 {
+		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "路径格式: /admin/provider/{name}/{action}"})
+		return
+	}
+	name := models.ProviderKind(parts[0])
+	action := parts[1]
+	clientIP := requestIP(r)
+
+	if !h.balancer.HasProvider(name) {
+		writeJSON(w, http.StatusNotFound, map[string]string{"error": "provider 不存在: " + string(name)})
+		return
+	}
+
+	switch action {
+	case "enable":
+		h.balancer.EnableProvider(name)
+		slog.Info("管理: 启用 provider", "provider", name, "from", clientIP)
+		writeJSON(w, http.StatusOK, map[string]string{"status": "enabled", "provider": string(name)})
+	case "disable":
+		h.balancer.DisableProvider(name)
+		slog.Info("管理: 禁用 provider", "provider", name, "from", clientIP)
+		writeJSON(w, http.StatusOK, map[string]string{"status": "disabled", "provider": string(name)})
+	default:
+		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "未知操作: " + action + "（可用: enable, disable）"})
+	}
+}
+
+// handleCacheClear 清空缓存。
+// POST /admin/cache/clear
+func (h *Handler) handleCacheClear(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+	h.cache.Clear()
+	slog.Info("管理: 缓存已清空", "from", requestIP(r))
+	writeJSON(w, http.StatusOK, map[string]string{"status": "cleared"})
+}
+
+// handleKeys 列出所有密钥状态。
+// GET /admin/keys
+func (h *Handler) handleKeys(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	type keyInfo struct {
+		Provider string `json:"provider"`
+		Enabled  bool   `json:"enabled"`
+	}
+
+	var keys []keyInfo
+	for _, p := range h.providerKinds {
+		keys = append(keys, keyInfo{
+			Provider: string(p),
+			Enabled:  h.balancer.IsProviderEnabled(p),
+		})
+	}
+
+	writeJSON(w, http.StatusOK, map[string]interface{}{
+		"keys": keys,
+	})
+}
+
+func writeJSON(w http.ResponseWriter, status int, data interface{}) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	json.NewEncoder(w).Encode(data)
+}
+
+// requestIP 从请求中提取客户端 IP。
+func requestIP(r *http.Request) string {
+	if fwd := r.Header.Get("X-Forwarded-For"); fwd != "" {
+		return fwd
+	}
+	// RemoteAddr 格式 "ip:port"，去掉端口
+	if host := r.RemoteAddr; host != "" {
+		for i := len(host) - 1; i >= 0; i-- {
+			if host[i] == ':' {
+				return host[:i]
+			}
+		}
+		return host
+	}
+	return "unknown"
+}

mcp/web-search/internal/mcp/handler.go

@@ -0,0 +1,240 @@
+// Package mcp 实现 MCP 协议的工具注册、调用处理（传输层无关）。
+package mcp
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"sort"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/balancer"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/cache"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/config"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/metrics"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// ToolDefinition MCP 工具定义。
+type ToolDefinition struct {
+	Name        string      `json:"name"`
+	Description string      `json:"description"`
+	InputSchema interface{} `json:"inputSchema"`
+}
+
+// CallToolRequest MCP tools/call JSON-RPC 参数。
+type CallToolRequest struct {
+	Name      string          `json:"name"`
+	Input     json.RawMessage `json:"input,omitempty"`
+	Arguments json.RawMessage `json:"arguments,omitempty"` // MCP 标准字段名
+}
+
+// CallToolResult MCP tools/call 响应体。
+type CallToolResult struct {
+	Content []ContentItem `json:"content"`
+	IsError bool          `json:"isError,omitempty"`
+}
+
+// ContentItem MCP 内容项。
+type ContentItem struct {
+	Type string `json:"type"`
+	Text string `json:"text"`
+}
+
+// Handler 搜索工具核心处理逻辑（传输层无关）。
+type Handler struct {
+	balancer      *balancer.LoadBalancer
+	cache         *cache.Manager
+	providerKinds []models.ProviderKind
+}
+
+func NewHandler(b *balancer.LoadBalancer, c *cache.Manager, providers []models.ProviderKind) *Handler {
+	return &Handler{
+		balancer:      b,
+		cache:         c,
+		providerKinds: providers,
+	}
+}
+
+// ReloadConfig 应用配置热重载变更。
+// 由 config.Reloader 在文件变更后调用，只处理 YAML 中可动态变更的字段。
+func (h *Handler) ReloadConfig(oldCfg, newCfg *config.Config) {
+	// Provider 启用/禁用
+	type pc struct {
+		name models.ProviderKind
+		old  config.ProviderConfig
+		new  config.ProviderConfig
+	}
+	changes := []pc{
+		{models.ProviderTavily, oldCfg.Providers.Tavily, newCfg.Providers.Tavily},
+		{models.ProviderBrave, oldCfg.Providers.Brave, newCfg.Providers.Brave},
+	}
+	for _, c := range changes {
+		if !c.old.Enabled && c.new.Enabled {
+			h.balancer.EnableProvider(c.name)
+			slog.Info("配置热重载: 启用 provider", "name", c.name)
+		} else if c.old.Enabled && !c.new.Enabled {
+			h.balancer.DisableProvider(c.name)
+			slog.Info("配置热重载: 禁用 provider", "name", c.name)
+		}
+	}
+
+	// 缓存 TTL
+	if oldCfg.Cache.TTL != newCfg.Cache.TTL {
+		h.cache.SetTTL(newCfg.Cache.TTL)
+		slog.Info("配置热重载: 缓存 TTL 更新", "old", oldCfg.Cache.TTL, "new", newCfg.Cache.TTL)
+	}
+
+	// 负载均衡重试次数
+	if oldCfg.Balancer.RetryCount != newCfg.Balancer.RetryCount {
+		h.balancer.SetRetryCount(newCfg.Balancer.RetryCount)
+		slog.Info("配置热重载: 重试次数更新", "old", oldCfg.Balancer.RetryCount, "new", newCfg.Balancer.RetryCount)
+	}
+}
+
+// ToolDefinition 返回 web_search 工具定义（MCP tools/list 用）。
+func (h *Handler) ToolDefinition() ToolDefinition {
+	return ToolDefinition{
+		Name:        "web_search",
+		Description: "联网搜索，获取最新的网络信息。支持多搜索引擎。",
+		InputSchema: map[string]interface{}{
+			"type": "object",
+			"properties": map[string]interface{}{
+				"query": map[string]interface{}{
+					"type":        "string",
+					"description": "搜索关键词",
+				},
+				"max_results": map[string]interface{}{
+					"type":        "integer",
+					"default":     5,
+					"minimum":     1,
+					"maximum":     20,
+					"description": "最大返回结果数",
+				},
+				"mode": map[string]interface{}{
+					"type":        "string",
+					"enum":        []string{"first", "merge"},
+					"default":     "first",
+					"description": "搜索模式：first（首个成功返回，默认）、merge（并发搜索所有引擎，去重合并）",
+				},
+				"providers": map[string]interface{}{
+					"type": "array",
+					"items": map[string]interface{}{
+						"type": "string",
+					},
+					"description": "优先使用的搜索引擎（默认全部可用引擎）",
+				},
+			},
+			"required": []string{"query"},
+		},
+	}
+}
+
+// HandleSearch 执行搜索（被 stdio、SSE、HTTP 三种传输层共享）。
+func (h *Handler) HandleSearch(ctx context.Context, req *models.SearchRequest) *CallToolResult {
+	start := time.Now()
+
+	// 校验
+	if req.Query == "" {
+		metrics.SearchErrors.WithLabelValues("empty_query").Inc()
+		return errorResult("搜索关键词不能为空")
+	}
+	if req.MaxResults <= 0 {
+		req.MaxResults = 5
+	}
+	if req.MaxResults > 20 {
+		req.MaxResults = 20
+	}
+	if req.Mode == "" {
+		req.Mode = models.ModeFirst
+	}
+
+	// 查缓存（用空 provider 查跨 provider 缓存）
+	if cached := h.cache.Get(req, ""); cached != nil {
+		metrics.CacheHits.Inc()
+		metrics.SearchDuration.Observe(time.Since(start).Seconds())
+		return successResult(cached)
+	}
+	metrics.CacheMisses.Inc()
+
+	// 执行搜索
+	if req.Mode == models.ModeMerge {
+		return h.mergeSearch(ctx, req, start)
+	}
+
+	result, err := h.balancer.Search(ctx, req)
+	if err != nil {
+		metrics.SearchErrors.WithLabelValues("search_failed").Inc()
+		return errorResult(fmt.Sprintf("搜索失败: %v", err))
+	}
+
+	// 写入缓存
+	h.cache.Set(req, result.Provider, result)
+	metrics.SearchTotal.WithLabelValues(string(result.Provider)).Inc()
+
+	return successResult(result)
+}
+
+func successResult(result *models.SearchResult) *CallToolResult {
+	jsonBytes, _ := json.Marshal(result)
+	return &CallToolResult{
+		Content: []ContentItem{
+			{Type: "json", Text: string(jsonBytes)},
+		},
+	}
+}
+
+func errorResult(msg string) *CallToolResult {
+	errJSON, _ := json.Marshal(map[string]string{"error": msg})
+	return &CallToolResult{
+		IsError: true,
+		Content: []ContentItem{
+			{Type: "text", Text: string(errJSON)},
+		},
+	}
+}
+
+// mergeSearch 并发搜索所有 provider，合并去重后返回。
+func (h *Handler) mergeSearch(ctx context.Context, req *models.SearchRequest, start time.Time) *CallToolResult {
+	results := h.balancer.SearchAll(ctx, req)
+	if len(results) == 0 {
+		metrics.SearchErrors.WithLabelValues("merge_no_results").Inc()
+		return errorResult("所有搜索引擎均未返回结果")
+	}
+
+	// 合并 + URL 去重
+	seen := make(map[string]bool)
+	var merged []models.ResultItem
+	for _, res := range results {
+		for _, item := range res.Results {
+			if seen[item.URL] {
+				continue
+			}
+			seen[item.URL] = true
+			merged = append(merged, item)
+		}
+	}
+
+	// 按 score 降序排序（无 score 的排最后）
+	sort.Slice(merged, func(i, j int) bool {
+		return merged[i].Score > merged[j].Score
+	})
+
+	// 截断到 max_results
+	if len(merged) > req.MaxResults {
+		merged = merged[:req.MaxResults]
+	}
+
+	final := &models.SearchResult{
+		Provider:   models.ProviderKind("merge"),
+		Query:      req.Query,
+		Results:    merged,
+		TotalCount: len(merged),
+		DurationMs: time.Since(start).Milliseconds(),
+		Cached:     false,
+	}
+
+	h.cache.Set(req, "", final)
+	return successResult(final)
+}

mcp/web-search/internal/mcp/handler_test.go

@@ -0,0 +1,43 @@
+package mcp
+
+import (
+	"context"
+	"testing"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/cache"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/config"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+func TestHandler_ToolDefinition(t *testing.T) {
+	h := NewHandler(nil, nil, nil)
+	def := h.ToolDefinition()
+	if def.Name != "web_search" {
+		t.Errorf("expected 'web_search', got '%s'", def.Name)
+	}
+	if def.Description == "" {
+		t.Error("expected non-empty description")
+	}
+}
+
+func TestHandler_HandleSearch_EmptyQuery(t *testing.T) {
+	c, _ := cache.New(config.CacheConfig{Enabled: false})
+	h := NewHandler(nil, c, nil)
+	result := h.HandleSearch(context.Background(), &models.SearchRequest{Query: ""})
+	if !result.IsError {
+		t.Fatal("expected error for empty query")
+	}
+}
+
+func TestHandler_HandleSearch_DefaultMaxResults(t *testing.T) {
+	req := &models.SearchRequest{Query: "test"}
+	if req.MaxResults <= 0 {
+		req.MaxResults = 5
+	}
+	if req.MaxResults > 20 {
+		req.MaxResults = 20
+	}
+	if req.MaxResults != 5 {
+		t.Errorf("expected default 5, got %d", req.MaxResults)
+	}
+}

mcp/web-search/internal/mcp/monitor.go

@@ -0,0 +1,242 @@
+package mcp
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// HandleMonitor 返回 HTML 监控面板（GET /）。
+func (h *Handler) HandleMonitor(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+
+	uptime := time.Since(startTime).Round(time.Second).String()
+
+	// Provider 表格行
+	var providerRows string
+	for _, p := range h.providerKinds {
+		counts := h.balancer.ActiveKeyCount()
+		activeKeys := counts[p]
+		enabled := h.balancer.IsProviderEnabled(p)
+		statusIcon := "🟢"
+		statusText := "启用"
+		if !enabled {
+			statusIcon = "🔴"
+			statusText = "禁用"
+		}
+		providerRows += fmt.Sprintf(`<tr>
+			<td>%s</td>
+			<td><span class="badge badge-provider">%s</span></td>
+			<td>%s <span class="status-text">%s</span></td>
+			<td class="num">%d</td>
+		</tr>`, statusIcon, p, statusIcon, statusText, activeKeys)
+	}
+
+	// 缓存统计
+	l1Hits, l2Hits, misses := h.cache.Stats()
+	hitRate := h.cache.HitRate()
+
+	html := fmt.Sprintf(`<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+<meta charset="UTF-8">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<title>博闻 · 监控面板</title>
+<style>
+  * { margin: 0; padding: 0; box-sizing: border-box; }
+  body {
+    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans SC", sans-serif;
+    background: #0f172a;
+    color: #e2e8f0;
+    padding: 24px;
+    line-height: 1.6;
+  }
+  .container { max-width: 960px; margin: 0 auto; }
+  h1 {
+    font-size: 24px;
+    font-weight: 600;
+    margin-bottom: 4px;
+    display: flex;
+    align-items: center;
+    gap: 12px;
+  }
+  h1 small {
+    font-size: 14px;
+    font-weight: 400;
+    color: #64748b;
+  }
+  .subtitle {
+    color: #64748b;
+    font-size: 14px;
+    margin-bottom: 24px;
+  }
+  .grid {
+    display: grid;
+    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
+    gap: 16px;
+    margin-bottom: 24px;
+  }
+  .card {
+    background: #1e293b;
+    border-radius: 12px;
+    padding: 16px 20px;
+    border: 1px solid #334155;
+  }
+  .card .label {
+    font-size: 12px;
+    color: #64748b;
+    text-transform: uppercase;
+    letter-spacing: 0.05em;
+    margin-bottom: 4px;
+  }
+  .card .value {
+    font-size: 28px;
+    font-weight: 700;
+    color: #38bdf8;
+  }
+  .card .value.green { color: #4ade80; }
+  .card .value.yellow { color: #fbbf24; }
+  .card .value.red { color: #f87171; }
+  .section-title {
+    font-size: 16px;
+    font-weight: 600;
+    margin-bottom: 12px;
+    color: #94a3b8;
+  }
+  table {
+    width: 100%%;
+    border-collapse: collapse;
+    background: #1e293b;
+    border-radius: 12px;
+    overflow: hidden;
+    border: 1px solid #334155;
+    margin-bottom: 24px;
+  }
+  th {
+    text-align: left;
+    padding: 12px 16px;
+    font-size: 12px;
+    color: #64748b;
+    text-transform: uppercase;
+    letter-spacing: 0.05em;
+    background: #1a2332;
+    border-bottom: 1px solid #334155;
+  }
+  td {
+    padding: 10px 16px;
+    border-bottom: 1px solid #1e293b;
+    font-size: 14px;
+  }
+  tr:last-child td { border-bottom: none; }
+  tr:hover { background: #243348; }
+  .num { text-align: right; font-variant-numeric: tabular-nums; }
+  .badge {
+    display: inline-block;
+    padding: 2px 8px;
+    border-radius: 4px;
+    font-size: 12px;
+    font-weight: 500;
+  }
+  .badge-provider {
+    background: #1e3a5f;
+    color: #93c5fd;
+  }
+  .status-text {
+    font-size: 13px;
+    color: #94a3b8;
+    margin-left: 4px;
+  }
+  a { color: #38bdf8; text-decoration: none; }
+  a:hover { text-decoration: underline; }
+  .links { margin-top: 16px; display: flex; gap: 16px; font-size: 14px; }
+  .footer { margin-top: 32px; padding-top: 16px; border-top: 1px solid #334155; color: #475569; font-size: 12px; }
+</style>
+</head>
+<body>
+<div class="container">
+  <h1>🔍 博闻 <small>Bowen Web Search</small></h1>
+  <div class="subtitle">运行时间 %s</div>
+
+  <div class="grid">
+    <div class="card">
+      <div class="label">Provider</div>
+      <div class="value">%d</div>
+    </div>
+    <div class="card">
+      <div class="label">活跃密钥</div>
+      <div class="value">%d</div>
+    </div>
+    <div class="card">
+      <div class="label">缓存命中率</div>
+      <div class="value %s">%d%%%%</div>
+    </div>
+    <div class="card">
+      <div class="label">缓存条目</div>
+      <div class="value">%d</div>
+    </div>
+  </div>
+
+  <div class="section-title">📡 Provider 状态</div>
+  <table>
+    <thead>
+      <tr><th>状态</th><th>名称</th><th>开关</th><th class="num">活跃密钥</th></tr>
+    </thead>
+    <tbody>%s</tbody>
+  </table>
+
+  <div class="section-title">💾 缓存统计</div>
+  <table>
+    <thead>
+      <tr><th>指标</th><th class="num">值</th></tr>
+    </thead>
+    <tbody>
+      <tr><td>L1 命中（内存 LRU）</td><td class="num">%d</td></tr>
+      <tr><td>L2 命中（Redis）</td><td class="num">%d</td></tr>
+      <tr><td>未命中</td><td class="num">%d</td></tr>
+      <tr><td>总命中率</td><td class="num">%.1f%%%%</td></tr>
+    </tbody>
+  </table>
+
+  <div class="links">
+    <span>🔗</span>
+    <a href="/status">/status (JSON)</a>
+    <a href="/admin/keys">/admin/keys</a>
+    <a href="/health">/health</a>
+  </div>
+
+  <div class="footer">博闻 v2.0.0 · 数据实时 · 页面每 30 秒刷新</div>
+</div>
+<script>setTimeout(function(){ location.reload(); }, 30000);</script>
+</body>
+</html>`,
+		uptime,
+		len(h.providerKinds),
+		sumActiveKeys(h.balancer.ActiveKeyCount()),
+		hitRateColor(hitRate),
+		int(hitRate*100),
+		l1Hits+l2Hits+misses,
+		providerRows,
+		l1Hits, l2Hits, misses, hitRate*100,
+	)
+
+	fmt.Fprint(w, html)
+}
+
+func sumActiveKeys(m map[models.ProviderKind]int) int {
+	s := 0
+	for _, v := range m {
+		s += v
+	}
+	return s
+}
+
+func hitRateColor(rate float64) string {
+	if rate >= 0.6 {
+		return "green"
+	} else if rate >= 0.3 {
+		return "yellow"
+	}
+	return "red"
+}

mcp/web-search/internal/mcp/sse.go

@@ -0,0 +1,101 @@
+package mcp
+
+import (
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"net/http"
+	"time"
+)
+
+// LoggingMiddleware 记录 HTTP 请求的源 IP、方法、路径和处理耗时。
+func LoggingMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		start := time.Now()
+		ip := r.RemoteAddr
+		if fwd := r.Header.Get("X-Forwarded-For"); fwd != "" {
+			ip = fwd
+		}
+		method := r.Method
+		path := r.URL.Path
+		next.ServeHTTP(w, r)
+		slog.Info("HTTP",
+			"method", method,
+			"path", path,
+			"from", ip,
+			"ms", time.Since(start).Milliseconds(),
+		)
+	})
+}
+
+// ServeHTTP 启动 Streamable HTTP 传输模式的 MCP 服务。
+//
+// 传输协议：MCP Streamable HTTP（JSON-RPC over HTTP POST /）
+// POST / → MCP 处理，GET / → 帮助页
+func (h *Handler) ServeHTTP(addr string) error {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", h.handleRoot)
+	// 管理端点
+	mux.HandleFunc("/health", h.HandleHealth)
+	mux.HandleFunc("/status", h.handleStatus)
+	h.registerAdminRoutes(mux)
+
+	slog.Info("博闻 HTTP 服务启动", "addr", addr, "providers", h.providerKinds)
+	return http.ListenAndServe(addr, LoggingMiddleware(mux))
+}
+
+// handleRoot MCP 服务根路径。
+// POST → MCP Streamable HTTP（JSON-RPC 2.0）
+// GET  → 帮助页
+func (h *Handler) handleRoot(w http.ResponseWriter, r *http.Request) {
+	if r.Method == http.MethodPost {
+		h.handleStreamableHTTP(w, r)
+		return
+	}
+	if r.URL.Path != "/" {
+		http.NotFound(w, r)
+		return
+	}
+	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+	fmt.Fprint(w, `博闻 Bowen · MCP Web Search
+
+传输协议：
+  POST /                        MCP Streamable HTTP（JSON-RPC 2.0，单端点）
+
+管理端点：
+  GET  /health                存活探针
+  GET  /status                系统状态
+  GET  /admin/keys            密钥状态
+  PUT  /admin/provider/:name/enable   启用 provider
+  PUT  /admin/provider/:name/disable  禁用 provider
+  POST /admin/cache/clear             清空缓存
+
+监控面板（metrics 端口）：
+  GET  /        HTML 仪表盘
+  GET  /metrics Prometheus 原始指标
+
+Stdio 模式：go run ./cmd/server --stdio
+`)
+}
+
+// handleStreamableHTTP MCP Streamable HTTP 传输端点。
+// 接收 JSON-RPC 2.0 POST 请求，返回 JSON-RPC 响应。
+// 现阶段返回完整响应（非流式），后续可扩展为 text/event-stream 流式传输。
+func (h *Handler) handleStreamableHTTP(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	var req JSONRPCRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusBadRequest)
+		json.NewEncoder(w).Encode(jsonRPCError(nil, -32700, "Parse error"))
+		return
+	}
+
+	resp := h.handleJSONRPC(req)
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(resp)
+}

mcp/web-search/internal/mcp/status.go

@@ -0,0 +1,75 @@
+package mcp
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+)
+
+// SystemStatus 博闻系统状态（通过 /status 或管理 API 查询）。
+type SystemStatus struct {
+	Version   string           `json:"version"`
+	Uptime    string           `json:"uptime"`
+	Providers []ProviderStatus `json:"providers"`
+	Cache     CacheStats       `json:"cache"`
+}
+
+// ProviderStatus provider 状态摘要。
+type ProviderStatus struct {
+	Name       string `json:"name"`
+	ActiveKeys int    `json:"active_keys"`
+	Enabled    bool   `json:"enabled"`
+}
+
+// CacheStats 缓存状态摘要。
+type CacheStats struct {
+	Enabled bool    `json:"enabled"`
+	L1Hits  int64   `json:"l1_hits"`
+	L2Hits  int64   `json:"l2_hits"`
+	Misses  int64   `json:"misses"`
+	HitRate float64 `json:"hit_rate"`
+}
+
+// startTime 记录博闻启动时间，用于 /status 的 uptime 计算。
+var startTime = time.Now()
+
+// HandleHealth 存活探针（GET /health → 200）。
+func (h *Handler) HandleHealth(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(map[string]string{"status": "ok"})
+}
+
+// handleStatus 系统状态（GET /status → SystemStatus）。
+func (h *Handler) handleStatus(w http.ResponseWriter, r *http.Request) {
+	// Provider 状态
+	var providers []ProviderStatus
+	for _, p := range h.providerKinds {
+		counts := h.balancer.ActiveKeyCount()
+		activeKeys := counts[p]
+		providers = append(providers, ProviderStatus{
+			Name:       string(p),
+			ActiveKeys: activeKeys,
+			Enabled:    activeKeys > 0,
+		})
+	}
+
+	// 缓存状态
+	l1Hits, l2Hits, misses := h.cache.Stats()
+	cacheStats := CacheStats{
+		Enabled: true,
+		L1Hits:  l1Hits,
+		L2Hits:  l2Hits,
+		Misses:  misses,
+		HitRate: h.cache.HitRate(),
+	}
+
+	status := SystemStatus{
+		Version:   "2.0.0",
+		Uptime:    time.Since(startTime).Round(time.Second).String(),
+		Providers: providers,
+		Cache:     cacheStats,
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(status)
+}

mcp/web-search/internal/mcp/stdio.go

@@ -0,0 +1,111 @@
+package mcp
+
+import (
+	"bufio"
+	"context"
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"os"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// JSONRPCRequest JSON-RPC 2.0 请求。
+type JSONRPCRequest struct {
+	JSONRPC string          `json:"jsonrpc"`
+	ID      *int            `json:"id"`
+	Method  string          `json:"method"`
+	Params  json.RawMessage `json:"params,omitempty"`
+}
+
+// JSONRPCResponse JSON-RPC 2.0 响应。
+type JSONRPCResponse struct {
+	JSONRPC string      `json:"jsonrpc"`
+	ID      *int        `json:"id"`
+	Result  interface{} `json:"result,omitempty"`
+	Error   *RPCError   `json:"error,omitempty"`
+}
+
+// RPCError JSON-RPC 错误。
+type RPCError struct {
+	Code    int    `json:"code"`
+	Message string `json:"message"`
+}
+
+// ServeStdio 通过 stdin/stdout 提供 MCP JSON-RPC 服务。
+func (h *Handler) ServeStdio() {
+	slog.Info("博闻 stdio 模式启动", "providers", h.providerKinds)
+	reader := bufio.NewReader(os.Stdin)
+	encoder := json.NewEncoder(os.Stdout)
+
+	for {
+		line, err := reader.ReadString('\n')
+		if err != nil {
+			slog.Error("stdio read error", "error", err)
+			return
+		}
+
+		var req JSONRPCRequest
+		if err := json.Unmarshal([]byte(line), &req); err != nil {
+			slog.Warn("stdio parse error", "error", err)
+			continue
+		}
+
+		resp := h.handleJSONRPC(req)
+		if err := encoder.Encode(resp); err != nil {
+			slog.Error("stdio write error", "error", err)
+		}
+	}
+}
+
+func (h *Handler) handleJSONRPC(req JSONRPCRequest) JSONRPCResponse {
+	switch req.Method {
+	case "tools/list":
+		return JSONRPCResponse{
+			JSONRPC: "2.0",
+			ID:      req.ID,
+			Result: map[string]interface{}{
+				"tools": []ToolDefinition{h.ToolDefinition()},
+			},
+		}
+
+	case "tools/call":
+		var callReq CallToolRequest
+		if err := json.Unmarshal(req.Params, &callReq); err != nil {
+			return jsonRPCError(req.ID, -32602, "Invalid params")
+		}
+		if callReq.Name != "web_search" {
+			return jsonRPCError(req.ID, -32601, fmt.Sprintf("Tool not found: %s", callReq.Name))
+		}
+
+		// 优先使用 MCP 标准 arguments 字段，兼容旧 input 字段
+		rawInput := callReq.Arguments
+		if len(rawInput) == 0 {
+			rawInput = callReq.Input
+		}
+
+		var searchReq models.SearchRequest
+		if err := json.Unmarshal(rawInput, &searchReq); err != nil {
+			return jsonRPCError(req.ID, -32602, "Invalid search request parameters: "+err.Error())
+		}
+
+		result := h.HandleSearch(context.Background(), &searchReq)
+		return JSONRPCResponse{
+			JSONRPC: "2.0",
+			ID:      req.ID,
+			Result:  result,
+		}
+
+	default:
+		return jsonRPCError(req.ID, -32601, fmt.Sprintf("Method not found: %s", req.Method))
+	}
+}
+
+func jsonRPCError(id *int, code int, msg string) JSONRPCResponse {
+	return JSONRPCResponse{
+		JSONRPC: "2.0",
+		ID:      id,
+		Error:   &RPCError{Code: code, Message: msg},
+	}
+}

mcp/web-search/internal/metrics/metrics.go

@@ -0,0 +1,69 @@
+// Package metrics 定义 Prometheus 监控指标。
+package metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+)
+
+var (
+	// SearchTotal 按 provider 统计搜索请求总数。
+	SearchTotal = promauto.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "bowen_search_total",
+			Help: "Total search requests by provider.",
+		},
+		[]string{"provider"},
+	)
+
+	// SearchDuration 搜索请求耗时直方图。
+	SearchDuration = promauto.NewHistogram(
+		prometheus.HistogramOpts{
+			Name:    "bowen_search_duration_seconds",
+			Help:    "Search request duration in seconds.",
+			Buckets: prometheus.DefBuckets,
+		},
+	)
+
+	// SearchErrors 按原因统计搜索错误。
+	SearchErrors = promauto.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "bowen_search_errors_total",
+			Help: "Search errors by reason.",
+		},
+		[]string{"reason"},
+	)
+
+	// CacheHits 缓存命中总数。
+	CacheHits = promauto.NewCounter(
+		prometheus.CounterOpts{
+			Name: "bowen_cache_hits_total",
+			Help: "Total cache hits.",
+		},
+	)
+
+	// CacheMisses 缓存未命中总数。
+	CacheMisses = promauto.NewCounter(
+		prometheus.CounterOpts{
+			Name: "bowen_cache_misses_total",
+			Help: "Total cache misses.",
+		},
+	)
+
+	// CacheHitsL2 Redis 二级缓存命中数。
+	CacheHitsL2 = promauto.NewCounter(
+		prometheus.CounterOpts{
+			Name: "bowen_cache_hits_l2_total",
+			Help: "L2 (Redis) cache hits.",
+		},
+	)
+
+	// ActiveKeys 各 provider 的活跃密钥数。
+	ActiveKeys = promauto.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "bowen_active_keys",
+			Help: "Number of active API keys by provider.",
+		},
+		[]string{"provider"},
+	)
+)

mcp/web-search/internal/models/types.go

@@ -0,0 +1,45 @@
+// Package models 定义博闻的数据类型。
+package models
+
+// ProviderKind 搜索提供商枚举。
+type ProviderKind string
+
+const (
+	ProviderTavily ProviderKind = "tavily"
+	ProviderBrave  ProviderKind = "brave"
+)
+
+// SearchMode 搜索结果聚合模式。
+type SearchMode string
+
+const (
+	ModeFirst SearchMode = "first" // 首个成功返回（低延迟，默认）
+	ModeMerge SearchMode = "merge" // 合并多 provider 结果（高召回）
+)
+
+// SearchRequest MCP 工具入参。
+type SearchRequest struct {
+	Query      string     `json:"query"`
+	MaxResults int        `json:"max_results"`
+	Providers  []string   `json:"providers,omitempty"`
+	Mode       SearchMode `json:"mode,omitempty"`
+}
+
+// SearchResult 统一搜索响应。
+type SearchResult struct {
+	Provider   ProviderKind `json:"provider"`
+	Query      string       `json:"query"`
+	Results    []ResultItem `json:"results"`
+	TotalCount int          `json:"total_count"`
+	DurationMs int64        `json:"duration_ms"`
+	Cached     bool         `json:"cached"`
+}
+
+// ResultItem 单条搜索结果。
+type ResultItem struct {
+	Title       string  `json:"title"`
+	URL         string  `json:"url"`
+	Snippet     string  `json:"snippet"`
+	PublishedAt string  `json:"published_at,omitempty"`
+	Score       float64 `json:"score,omitempty"`
+}

mcp/web-search/internal/providers/brave.go

@@ -0,0 +1,125 @@
+package providers
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+const braveAPIBase = "https://api.search.brave.com"
+
+// BraveProvider 实现 SearchProvider。
+type BraveProvider struct {
+	client     *http.Client
+	apiBase    string
+	maxResults int
+}
+
+func NewBraveProvider(timeout time.Duration, maxResults int) *BraveProvider {
+	return &BraveProvider{
+		client: &http.Client{
+			Timeout: timeout,
+		},
+		apiBase:    braveAPIBase,
+		maxResults: maxResults,
+	}
+}
+
+func (b *BraveProvider) Name() models.ProviderKind {
+	return models.ProviderBrave
+}
+
+func (b *BraveProvider) MaxResults() int {
+	return b.maxResults
+}
+
+type braveWebResult struct {
+	Title       string `json:"title"`
+	URL         string `json:"url"`
+	Description string `json:"description"`
+	Age         string `json:"age"`
+}
+
+type braveResponse struct {
+	Web struct {
+		Results []braveWebResult `json:"results"`
+	} `json:"web"`
+}
+
+func (b *BraveProvider) Search(ctx context.Context, apiKey string, req *models.SearchRequest) (*models.SearchResult, error) {
+	maxRes := req.MaxResults
+	if maxRes <= 0 || maxRes > b.maxResults {
+		maxRes = b.maxResults
+	}
+
+	u, _ := url.Parse(b.apiBase + "/res/v1/web/search")
+	q := u.Query()
+	q.Set("q", req.Query)
+	q.Set("count", fmt.Sprintf("%d", maxRes))
+	u.RawQuery = q.Encode()
+
+	httpReq, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), nil)
+	if err != nil {
+		return nil, fmt.Errorf("brave: create request: %w", err)
+	}
+	httpReq.Header.Set("Accept", "application/json")
+	httpReq.Header.Set("X-Subscription-Token", apiKey)
+
+	start := time.Now()
+	resp, err := b.client.Do(httpReq)
+	duration := time.Since(start)
+	if err != nil {
+		return nil, fmt.Errorf("brave: do request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	raw, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("brave: read body: %w", err)
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("brave: status %d: %s", resp.StatusCode, string(raw))
+	}
+
+	var br braveResponse
+	if err := json.Unmarshal(raw, &br); err != nil {
+		return nil, fmt.Errorf("brave: decode: %w", err)
+	}
+
+	items := make([]models.ResultItem, 0, len(br.Web.Results))
+	for _, r := range br.Web.Results {
+		items = append(items, models.ResultItem{
+			Title:       r.Title,
+			URL:         r.URL,
+			Snippet:     r.Description,
+			PublishedAt: r.Age,
+		})
+	}
+
+	return &models.SearchResult{
+		Provider:   models.ProviderBrave,
+		Query:      req.Query,
+		Results:    items,
+		TotalCount: len(items),
+		DurationMs: duration.Milliseconds(),
+		Cached:     false,
+	}, nil
+}
+
+func (b *BraveProvider) HealthCheck(ctx context.Context) error {
+	var d net.Dialer
+	conn, err := d.DialContext(ctx, "tcp", "api.search.brave.com:443")
+	if err != nil {
+		return err
+	}
+	conn.Close()
+	return nil
+}

mcp/web-search/internal/providers/brave_test.go

@@ -0,0 +1,53 @@
+package providers
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+func TestBraveProvider_Search_Success(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("X-Subscription-Token") == "" {
+			t.Error("missing subscription token header")
+		}
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte(`{
+			"web": {
+				"results": [
+					{"title": "Brave Result", "url": "https://brave.com/1", "description": "Brave snippet"}
+				]
+			}
+		}`))
+	}))
+	defer ts.Close()
+
+	p := &BraveProvider{
+		client:     ts.Client(),
+		apiBase:    ts.URL,
+		maxResults: 10,
+	}
+
+	r, err := p.Search(context.Background(), "test-key", &models.SearchRequest{Query: "test"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if r.TotalCount != 1 {
+		t.Fatalf("expected 1 result, got %d", r.TotalCount)
+	}
+	if r.Results[0].Title != "Brave Result" {
+		t.Errorf("expected 'Brave Result', got '%s'", r.Results[0].Title)
+	}
+}
+
+func TestBraveProvider_Name(t *testing.T) {
+	p := NewBraveProvider(5*time.Second, 10)
+	if p.Name() != models.ProviderBrave {
+		t.Errorf("expected brave, got %s", p.Name())
+	}
+}

mcp/web-search/internal/providers/provider.go

@@ -0,0 +1,20 @@
+// Package providers 封装搜索提供商适配。
+package providers
+
+import (
+	"context"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// SearchProvider 搜索提供商接口。
+type SearchProvider interface {
+	// Name 返回提供商标识。
+	Name() models.ProviderKind
+	// Search 执行搜索。apiKey 由负载均衡器传入，provider 本身不管理密钥。
+	Search(ctx context.Context, apiKey string, req *models.SearchRequest) (*models.SearchResult, error)
+	// HealthCheck 健康检查。
+	HealthCheck(ctx context.Context) error
+	// MaxResults 返回单次搜索最大数量。
+	MaxResults() int
+}

mcp/web-search/internal/providers/registry.go

@@ -0,0 +1,123 @@
+package providers
+
+import (
+	"fmt"
+	"log/slog"
+	"sync"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/config"
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+// Registry 管理多 provider 注册和查询。
+type Registry struct {
+	mu        sync.RWMutex
+	providers map[models.ProviderKind]SearchProvider
+}
+
+func NewRegistry() *Registry {
+	return &Registry{
+		providers: make(map[models.ProviderKind]SearchProvider),
+	}
+}
+
+// Register 注册 provider。
+func (r *Registry) Register(p SearchProvider) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.providers[p.Name()] = p
+}
+
+// Get 按名称获取 provider。
+func (r *Registry) Get(name models.ProviderKind) (SearchProvider, bool) {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+	p, ok := r.providers[name]
+	return p, ok
+}
+
+// All 返回所有已注册 provider。
+func (r *Registry) All() []SearchProvider {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+	out := make([]SearchProvider, 0, len(r.providers))
+	for _, p := range r.providers {
+		out = append(out, p)
+	}
+	return out
+}
+
+// Names 返回所有已注册的 provider 名称。
+func (r *Registry) Names() []models.ProviderKind {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+	out := make([]models.ProviderKind, 0, len(r.providers))
+	for name := range r.providers {
+		out = append(out, name)
+	}
+	return out
+}
+
+// SetupFromConfig 根据配置创建并注册所有启用的 provider。
+func SetupFromConfig(cfg *config.Config) (*Registry, error) {
+	reg := NewRegistry()
+
+	if cfg.Providers.Tavily.Enabled {
+		if len(cfg.Providers.Tavily.APIKeys) == 0 {
+			slog.Warn("tavily: enabled but no API keys configured, skipping")
+		} else {
+			reg.Register(NewTavilyProvider(cfg.Providers.Tavily.Timeout, cfg.Providers.Tavily.MaxResults))
+		}
+	}
+	if cfg.Providers.Brave.Enabled {
+		if len(cfg.Providers.Brave.APIKeys) == 0 {
+			slog.Warn("brave: enabled but no API keys configured, skipping")
+		} else {
+			reg.Register(NewBraveProvider(cfg.Providers.Brave.Timeout, cfg.Providers.Brave.MaxResults))
+		}
+	}
+
+	if len(reg.Names()) == 0 {
+		return nil, fmt.Errorf("no providers enabled or configured")
+	}
+	return reg, nil
+}
+
+// SetupFromConfigWithOverrides 从配置创建注册中心，并允许使用显式 provider 配置覆盖配置文件。
+// 本函数方便测试和动态配置场景。
+func SetupFromConfigWithOverrides(
+	cfg *config.Config,
+	overrideTimeout time.Duration,
+	overrideMaxResults int,
+) (*Registry, error) {
+	reg := NewRegistry()
+
+	if cfg.Providers.Tavily.Enabled && len(cfg.Providers.Tavily.APIKeys) > 0 {
+		t := cfg.Providers.Tavily.Timeout
+		m := cfg.Providers.Tavily.MaxResults
+		if overrideTimeout > 0 {
+			t = overrideTimeout
+		}
+		if overrideMaxResults > 0 {
+			m = overrideMaxResults
+		}
+		reg.Register(NewTavilyProvider(t, m))
+	}
+	if cfg.Providers.Brave.Enabled && len(cfg.Providers.Brave.APIKeys) > 0 {
+		t := cfg.Providers.Brave.Timeout
+		m := cfg.Providers.Brave.MaxResults
+		if overrideTimeout > 0 {
+			t = overrideTimeout
+		}
+		if overrideMaxResults > 0 {
+			m = overrideMaxResults
+		}
+		reg.Register(NewBraveProvider(t, m))
+	}
+
+	if len(reg.Names()) == 0 {
+		return nil, fmt.Errorf("no providers enabled or configured")
+	}
+	return reg, nil
+}

mcp/web-search/internal/providers/registry_test.go

@@ -0,0 +1,63 @@
+package providers
+
+import (
+	"context"
+	"testing"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+type mockProvider struct {
+	name models.ProviderKind
+}
+
+func (m *mockProvider) Name() models.ProviderKind { return m.name }
+func (m *mockProvider) Search(ctx context.Context, s string, req *models.SearchRequest) (*models.SearchResult, error) {
+	return &models.SearchResult{Provider: m.name, Query: req.Query}, nil
+}
+func (m *mockProvider) HealthCheck(ctx context.Context) error { return nil }
+func (m *mockProvider) MaxResults() int                       { return 10 }
+
+func TestRegistry_RegisterAndGet(t *testing.T) {
+	r := NewRegistry()
+	m := &mockProvider{name: models.ProviderTavily}
+	r.Register(m)
+
+	got, ok := r.Get(models.ProviderTavily)
+	if !ok {
+		t.Fatal("expected to find provider")
+	}
+	if got.Name() != models.ProviderTavily {
+		t.Errorf("expected tavily, got %s", got.Name())
+	}
+}
+
+func TestRegistry_All(t *testing.T) {
+	r := NewRegistry()
+	r.Register(&mockProvider{name: models.ProviderTavily})
+	r.Register(&mockProvider{name: models.ProviderBrave})
+
+	all := r.All()
+	if len(all) != 2 {
+		t.Errorf("expected 2 providers, got %d", len(all))
+	}
+}
+
+func TestRegistry_GetMissing(t *testing.T) {
+	r := NewRegistry()
+	_, ok := r.Get(models.ProviderBrave)
+	if ok {
+		t.Fatal("expected missing provider")
+	}
+}
+
+func TestRegistry_Names(t *testing.T) {
+	r := NewRegistry()
+	r.Register(&mockProvider{name: models.ProviderTavily})
+	r.Register(&mockProvider{name: models.ProviderBrave})
+
+	names := r.Names()
+	if len(names) != 2 {
+		t.Errorf("expected 2 names, got %d", len(names))
+	}
+}

mcp/web-search/internal/providers/tavily.go

@@ -0,0 +1,134 @@
+package providers
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+const tavilyAPIBase = "https://api.tavily.com"
+
+type tavilyRequest struct {
+	APIKey     string `json:"api_key"`
+	Query      string `json:"query"`
+	MaxResults int    `json:"max_results"`
+}
+
+type tavilyResponse struct {
+	Answer       string         `json:"answer"`
+	Query        string         `json:"query"`
+	ResponseTime float64        `json:"response_time"`
+	Results      []tavilyResult `json:"results"`
+}
+
+type tavilyResult struct {
+	Title       string  `json:"title"`
+	URL         string  `json:"url"`
+	Content     string  `json:"content"`
+	Score       float64 `json:"score"`
+	PublishedAt string  `json:"published_date"`
+}
+
+// TavilyProvider 实现 SearchProvider。
+type TavilyProvider struct {
+	client     *http.Client
+	apiBase    string
+	maxResults int
+}
+
+func NewTavilyProvider(timeout time.Duration, maxResults int) *TavilyProvider {
+	return &TavilyProvider{
+		client: &http.Client{
+			Timeout: timeout,
+		},
+		apiBase:    tavilyAPIBase,
+		maxResults: maxResults,
+	}
+}
+
+func (t *TavilyProvider) Name() models.ProviderKind {
+	return models.ProviderTavily
+}
+
+func (t *TavilyProvider) MaxResults() int {
+	return t.maxResults
+}
+
+func (t *TavilyProvider) Search(ctx context.Context, apiKey string, req *models.SearchRequest) (*models.SearchResult, error) {
+	maxRes := req.MaxResults
+	if maxRes <= 0 || maxRes > t.maxResults {
+		maxRes = t.maxResults
+	}
+
+	body := tavilyRequest{
+		APIKey:     apiKey,
+		Query:      req.Query,
+		MaxResults: maxRes,
+	}
+	payload, _ := json.Marshal(body)
+
+	httpReq, err := http.NewRequestWithContext(ctx, http.MethodPost, t.apiBase+"/search", bytes.NewReader(payload))
+	if err != nil {
+		return nil, fmt.Errorf("tavily: create request: %w", err)
+	}
+	httpReq.Header.Set("Content-Type", "application/json")
+
+	start := time.Now()
+	resp, err := t.client.Do(httpReq)
+	duration := time.Since(start)
+	if err != nil {
+		return nil, fmt.Errorf("tavily: do request: %w", err)
+	}
+	defer resp.Body.Close()
+
+	raw, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("tavily: read body: %w", err)
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("tavily: status %d: %s", resp.StatusCode, string(raw))
+	}
+
+	var tr tavilyResponse
+	if err := json.Unmarshal(raw, &tr); err != nil {
+		return nil, fmt.Errorf("tavily: decode response: %w", err)
+	}
+
+	items := make([]models.ResultItem, 0, len(tr.Results))
+	for _, r := range tr.Results {
+		items = append(items, models.ResultItem{
+			Title:       r.Title,
+			URL:         r.URL,
+			Snippet:     r.Content,
+			Score:       r.Score,
+			PublishedAt: r.PublishedAt,
+		})
+	}
+
+	return &models.SearchResult{
+		Provider:   models.ProviderTavily,
+		Query:      req.Query,
+		Results:    items,
+		TotalCount: len(items),
+		DurationMs: duration.Milliseconds(),
+		Cached:     false,
+	}, nil
+}
+
+func (t *TavilyProvider) HealthCheck(ctx context.Context) error {
+	var d net.Dialer
+	conn, err := d.DialContext(ctx, "tcp", "api.tavily.com:443")
+	if err != nil {
+		return err
+	}
+	conn.Close()
+	return nil
+}

mcp/web-search/internal/providers/tavily_test.go

@@ -0,0 +1,71 @@
+package providers
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/chenxin/hunjing/mcp/web-search/internal/models"
+)
+
+func TestTavilyProvider_Search_Success(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/search" {
+			t.Errorf("unexpected path: %s", r.URL.Path)
+		}
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte(`{
+			"query": "test",
+			"results": [
+				{"title": "Result 1", "url": "https://example.com/1", "content": "Content 1", "score": 0.95}
+			]
+		}`))
+	}))
+	defer ts.Close()
+
+	p := &TavilyProvider{
+		client:     ts.Client(),
+		apiBase:    ts.URL,
+		maxResults: 10,
+	}
+
+	result, err := p.Search(context.Background(), "test-key", &models.SearchRequest{Query: "test"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if result.TotalCount != 1 {
+		t.Fatalf("expected 1 result, got %d", result.TotalCount)
+	}
+	if result.Results[0].Title != "Result 1" {
+		t.Errorf("expected 'Result 1', got '%s'", result.Results[0].Title)
+	}
+}
+
+func TestTavilyProvider_Search_HTTPError(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusUnauthorized)
+		w.Write([]byte(`{"error": "invalid api key"}`))
+	}))
+	defer ts.Close()
+
+	p := &TavilyProvider{
+		client:     ts.Client(),
+		apiBase:    ts.URL,
+		maxResults: 10,
+	}
+
+	_, err := p.Search(context.Background(), "bad-key", &models.SearchRequest{Query: "test"})
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+}
+
+func TestTavilyProvider_Name(t *testing.T) {
+	p := NewTavilyProvider(5*time.Second, 10)
+	if p.Name() != models.ProviderTavily {
+		t.Errorf("expected tavily, got %s", p.Name())
+	}
+}