diff --git a/service/prompt/prompt_build_service.go b/service/prompt/prompt_build_service.go
index 284db31..b2d772b 100644
--- a/service/prompt/prompt_build_service.go
+++ b/service/prompt/prompt_build_service.go
@@ -38,7 +38,7 @@ func buildNodeTypeRequest(ctx context.Context, req *dto.ComposeMessagesReq, chat
 
 // buildStructTypeRequest 构建结构体类型请求（BuildType=3）
 func buildStructTypeRequest(ctx context.Context, req *dto.ComposeMessagesReq, chatModel *gateway.AsynchModel, ir *IR) (map[string]any, error) {
-	customPrompt := gjson.New(req.UserForm).Get("0.prompt").String()
+	customPrompt := req.UserPrompt
 	ir.AddSystem(customPrompt)
 	ir.AddUser(buildUserPrompt(ctx, req))
 	return compileToProviderRequest(ctx, ir, chatModel, req, customPrompt)