diff --git a/apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/merge.rs b/apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/merge.rs
index 2e125ee21..1d44e6d93 100644
--- a/apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/merge.rs
+++ b/apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/merge.rs
@@ -1,7 +1,8 @@
 use crate::config::build_game_creator_llm_client_from_llm_config;
 use crate::config::load_game_creator_app_config;
 use crate::ui_editor::commands::utils::{
-    request_ui_editor_llm, required_tool_arguments, strict_json_schema,
+    parse_limited_llm_tool_arguments, request_ui_editor_llm, required_tool_call_arguments,
+    strict_json_schema,
 };
 use crate::ui_editor::state::{State, UITree};
 use platform_llm::{LlmFunctionTool, LlmMessage, LlmRunRequest, LlmToolChoice};
@@ -487,7 +488,11 @@ pub(crate) async fn merge_ui_impl_with_provider(
         app_log!("ui_merge.error stage=llm_request error={error}");
         format!("UI 树合并失败：{error}")
     })?;
-    let arguments = required_tool_arguments(&response, MERGE_TOOL_NAME).map_err(|error| {
+    let arguments = required_tool_call_arguments(&response, MERGE_TOOL_NAME).map_err(|error| {
+        app_log!("ui_merge.error stage=parse_tool_call reason=missing_tool_call error={error}");
+        format!("LLM 未返回 {MERGE_TOOL_NAME} 工具调用")
+    })?;
+    let arguments = parse_limited_llm_tool_arguments(arguments).map_err(|error| {
         app_log!("ui_merge.error stage=parse_arguments error={error}");
         format!("UI 合并工具参数无效：{error}")
     })?;