diff --git a/internal/api/server.go b/internal/api/server.go
index c7505dc2..e0c92b3e 100644
--- a/internal/api/server.go
+++ b/internal/api/server.go
@@ -12,6 +12,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"reflect"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -990,14 +991,17 @@ func (s *Server) UpdateClients(cfg *config.Config) {
 		s.mgmt.SetAuthManager(s.handlers.AuthManager)
 	}
 
-	// Notify Amp module of config changes (for model mapping hot-reload)
-	if s.ampModule != nil {
-		log.Debugf("triggering amp module config update")
-		if err := s.ampModule.OnConfigUpdated(cfg); err != nil {
-			log.Errorf("failed to update Amp module config: %v", err)
+	// Notify Amp module only when Amp config has changed.
+	ampConfigChanged := oldCfg == nil || !reflect.DeepEqual(oldCfg.AmpCode, cfg.AmpCode)
+	if ampConfigChanged {
+		if s.ampModule != nil {
+			log.Debugf("triggering amp module config update")
+			if err := s.ampModule.OnConfigUpdated(cfg); err != nil {
+				log.Errorf("failed to update Amp module config: %v", err)
+			}
+		} else {
+			log.Warnf("amp module is nil, skipping config update")
 		}
-	} else {
-		log.Warnf("amp module is nil, skipping config update")
 	}
 
 	// Count client sources from configuration and auth store.
diff --git a/internal/config/config.go b/internal/config/config.go
index 839b7b05..5fd48408 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -923,6 +923,7 @@ func SaveConfigPreserveComments(configFile string, cfg *Config) error {
 	removeLegacyGenerativeLanguageKeys(original.Content[0])
 
 	pruneMappingToGeneratedKeys(original.Content[0], generated.Content[0], "oauth-excluded-models")
+	pruneMappingToGeneratedKeys(original.Content[0], generated.Content[0], "oauth-model-alias")
 
 	// Merge generated into original in-place, preserving comments/order of existing nodes.
 	mergeMappingPreserve(original.Content[0], generated.Content[0])