diff --git a/common/constants.go b/common/constants.go
index 2e95ea6..1dd4846 100644
--- a/common/constants.go
+++ b/common/constants.go
@@ -15,8 +15,6 @@ const (
 	MaxRequestBodySize    = 1024 * 1024
 	RateLimitRequests     = 100
 	RateLimitWindow       = time.Minute
-	MaxResponseTimes      = 100
-	MaxErrors             = 10
 	MaxConcurrentRequests = 10
 	CleanupInterval       = time.Hour
 	MaxModelNameLength    = 64
diff --git a/controller/tts.go b/controller/tts.go
index f9e869e..5ed6495 100644
--- a/controller/tts.go
+++ b/controller/tts.go
@@ -46,9 +46,6 @@ func resolveClientFormat(reqFmt string) string {
 		}
 		return strings.ToLower(reqFmt)
 	}
-	if reqFmt == "" {
-		return setting.TTSOptions.Format
-	}
 	return setting.TTSOptions.Format
 }
 
diff --git a/dto/tts.go b/dto/tts.go
index b0420cf..4568d15 100644
--- a/dto/tts.go
+++ b/dto/tts.go
@@ -58,15 +58,6 @@ type V3Usage struct {
 	TextWords int `json:"text_words"`
 }
 
-// ByteDanceTTSConfig 是 setting 包的全局 TTS 配置,目前只承载鉴权 / URL / 超时;
-// 完整的合成参数见 adapter/volcano.Options。
-type ByteDanceTTSConfig struct {
-	ApiKey     string
-	ResourceId string
-	URL        string
-	Timeout    time.Duration
-}
-
 // SynthesisResult 是火山适配器向 controller 返回的最终结果。
 // Format 与 AudioData 的实际编码一致;controller 据此设置响应 Content-Type。
 type SynthesisResult struct {
diff --git a/middleware/auth.go b/middleware/auth.go
index 95f6a37..59dc2e7 100644
--- a/middleware/auth.go
+++ b/middleware/auth.go
@@ -9,13 +9,6 @@ import (
 	"github.com/volcano-tts/tts-api/setting"
 )
 
-// InitAPIKeys 已在 setting.InitAuthConfig 中完成,这里保留为 no-op 以维持现有调用顺序。
-// 实际鉴权逻辑直接读 setting.Auth.APIKeys。
-func InitAPIKeys() {
-	// 配置由 setting 包统一加载,日志也由 setting.LogStartupSummary 输出。
-	_ = setting.Auth
-}
-
 func ValidateAPIKey(r *http.Request) bool {
 	if len(setting.Auth.APIKeys) == 0 {
 		return true
diff --git a/middleware/cors.go b/middleware/cors.go
index 79ba784..ce859d8 100644
--- a/middleware/cors.go
+++ b/middleware/cors.go
@@ -13,13 +13,6 @@ var (
 	corsMaxAgeHeader = "86400"
 )
 
-// InitCORSConfig 已在 setting.InitCORSConfig 中完成,这里保留为 no-op 以维持现有调用顺序。
-// 实际 CORS 匹配逻辑直接读 setting.CORS.Origins / setting.CORS.AllowAll。
-func InitCORSConfig() {
-	// 配置由 setting 包统一加载,日志也由 setting.LogStartupSummary 输出。
-	_ = setting.CORS
-}
-
 func isValidOrigin(origin string) bool {
 	if origin == "" || origin == "null" || origin == "nil" {
 		return false
diff --git a/middleware/ratelimit_instrumented.go b/middleware/ratelimit_instrumented.go
index a9e05ef..da8a5ab 100644
--- a/middleware/ratelimit_instrumented.go
+++ b/middleware/ratelimit_instrumented.go
@@ -1,10 +1,9 @@
 package middleware
 
-// 本文件提供带 metrics 埋点的限流 / 并发中间件版本;
-// 由于原 ratelimit_middleware.go 在本仓库的云盘同步下被永久占用,
-// 这里用独立实现覆盖路由使用入口,旧实现保留为未引用代码。
-//
-// 行为与原 ratelimit_middleware.go 完全一致,只是多了 metrics 调用。
+// 本文件提供带 metrics 埋点的限流 / 并发中间件版本。
+// 相比 router 实际使用的实现,本版本额外做了:
+//   - 加 metrics 埋点(限流拒绝 / 并发拒绝计数)
+//   - 仅对 /v1/ 下的业务请求生效,监控路径(/health /metrics /dashboard)不消耗配额
 
 import (
 	"log"
@@ -14,7 +13,7 @@ import (
 	"github.com/volcano-tts/tts-api/metrics"
 )
 
-// RateLimitWithMetrics 是 middleware.RateLimit 的可埋点版本。
+// RateLimitWithMetrics 是限流中间件,带埋点 + 路径过滤。
 func RateLimitWithMetrics(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		// 仅对 /v1/ 下的业务请求限流,/health /metrics /dashboard 等监控路径不限流
@@ -32,7 +31,7 @@ func RateLimitWithMetrics(next http.Handler) http.Handler {
 	})
 }
 
-// ConcurrencyLimitWithMetrics 是 middleware.ConcurrencyLimit 的可埋点版本。
+// ConcurrencyLimitWithMetrics 是并发控制中间件,带埋点 + 路径过滤。
 func ConcurrencyLimitWithMetrics(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		// 仅对 /v1/ 下的业务请求统计并发和加锁,监控路径不占用并发槽位
diff --git a/middleware/ratelimit_middleware.go b/middleware/ratelimit_middleware.go
deleted file mode 100644
index bbbb9f0..0000000
--- a/middleware/ratelimit_middleware.go
+++ /dev/null
@@ -1,32 +0,0 @@
-package middleware
-
-import (
-	"log"
-	"net/http"
-)
-
-func RateLimit(next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		clientIP := GetClientIP(r)
-		if !GlobalRateLimiter.Allow(clientIP) {
-			log.Printf("警告: 已超过IP速率限制，拒绝请求 - 客户端IP: %s", clientIP)
-			SendJSONError(w, http.StatusTooManyRequests, "Rate limit exceeded. Please try again later.", "rate_limit_error", "rate_limit_exceeded")
-			return
-		}
-		next.ServeHTTP(w, r)
-	})
-}
-
-func ConcurrencyLimit(next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		select {
-		case ConcurrencySem <- struct{}{}:
-			defer func() { <-ConcurrencySem }()
-			next.ServeHTTP(w, r)
-		default:
-			log.Printf("警告: 已达到最大并发请求数限制，拒绝请求 - 客户端IP: %s", GetClientIP(r))
-			SendJSONError(w, http.StatusServiceUnavailable, "Server is busy, maximum concurrent requests reached. Please try again later.", "concurrency_limit_error", "max_concurrent_requests")
-			return
-		}
-	})
-}
diff --git a/setting/config.go b/setting/config.go
index 2a1d202..38ea45f 100644
--- a/setting/config.go
+++ b/setting/config.go
@@ -10,7 +10,6 @@ import (
 
 	"github.com/volcano-tts/tts-api/adapter/volcano"
 	"github.com/volcano-tts/tts-api/common"
-	"github.com/volcano-tts/tts-api/dto"
 )
 
 // 全部环境变量读取的单一入口:其它包不允许直接 os.Getenv,只读这里的全局 Config。
@@ -317,7 +316,3 @@ func CheckStaticFiles() {
 		log.Println("警告: health.html 不存在,/dashboard 路由将返回 404")
 	}
 }
-
-// 保留 dto.ByteDanceTTSConfig 引用避免 import 警告;
-// 新代码不应再使用这个类型,设置已在 TTSOptions 中。
-var _ = dto.ByteDanceTTSConfig{}