diff --git a/backend/internal/pkg/antigravity/oauth.go b/backend/internal/pkg/antigravity/oauth.go
index f6ece2da..47c75142 100644
--- a/backend/internal/pkg/antigravity/oauth.go
+++ b/backend/internal/pkg/antigravity/oauth.go
@@ -38,9 +38,6 @@ const (
 		"https://www.googleapis.com/auth/cclog " +
 		"https://www.googleapis.com/auth/experimentsandconfigs"
 
-	// User-Agent（与 Antigravity-Manager 保持一致）
-	UserAgent = "antigravity/1.18.4 windows/amd64"
-
 	// Session 过期时间
 	SessionTTL = 30 * time.Minute