diff --git a/backend/internal/pkg/antigravity/claude_types.go b/backend/internal/pkg/antigravity/claude_types.go
index 34e6b1f4..01b805cd 100644
--- a/backend/internal/pkg/antigravity/claude_types.go
+++ b/backend/internal/pkg/antigravity/claude_types.go
@@ -54,9 +54,6 @@ type CustomToolSpec struct {
 	InputSchema map[string]any `json:"input_schema"`
 }
 
-// ClaudeCustomToolSpec 兼容旧命名（MCP custom 工具规格）
-type ClaudeCustomToolSpec = CustomToolSpec
-
 // SystemBlock system prompt 数组形式的元素
 type SystemBlock struct {
 	Type string `json:"type"`