diff --git a/internal/api/handlers/management/api_tools.go b/internal/api/handlers/management/api_tools.go
index de546ea820..4103006ff3 100644
--- a/internal/api/handlers/management/api_tools.go
+++ b/internal/api/handlers/management/api_tools.go
@@ -613,21 +613,15 @@ func tokenValueFromMetadata(metadata map[string]any) string {
 }
 
 func (h *Handler) authByIndex(authIndex string) *coreauth.Auth {
-	authIndex = strings.TrimSpace(authIndex)
-	if authIndex == "" || h == nil || h.authManager == nil {
-		return nil
-	}
-	auths := h.authManager.List()
-	for _, auth := range auths {
-		if auth == nil {
-			continue
-		}
-		auth.EnsureIndex()
-		if auth.Index == authIndex {
-			return auth
-		}
-	}
-	return nil
+    authIndex = strings.TrimSpace(authIndex)
+    if authIndex == "" || h == nil || h.authManager == nil {
+        return nil
+    }
+    // 使用直接查找替代 List() 全量拷贝
+    if auth, ok := h.authManager.GetByIndex(authIndex); ok {
+        return auth
+    }
+    return nil
 }
 
 func (h *Handler) apiCallTransport(auth *coreauth.Auth) http.RoundTripper {
diff --git a/sdk/cliproxy/auth/conductor.go b/sdk/cliproxy/auth/conductor.go
index b29e04db8c..241da31451 100644
--- a/sdk/cliproxy/auth/conductor.go
+++ b/sdk/cliproxy/auth/conductor.go
@@ -2879,3 +2879,22 @@ func (m *Manager) HttpRequest(ctx context.Context, auth *Auth, req *http.Request
 	}
 	return exec.HttpRequest(ctx, auth, req)
 }
+
+func (m *Manager) GetByIndex(index string) (*Auth, bool) {
+    index = strings.TrimSpace(index)
+    if index == "" {
+        return nil, false
+    }
+    m.mu.Lock()
+    defer m.mu.Unlock()
+    for _, auth := range m.auths {
+        if auth == nil {
+            continue
+        }
+        auth.EnsureIndex()
+        if auth.Index == index {
+            return auth.Clone(), true
+        }
+    }
+    return nil, false
+}