 In 423, a messenger of Laozi came and offered Kou a new text called the "Lutu Zhenjing" (Perfect Scripture of Registers and Charts), which is now lost, and appointed him as the new Celestial Master.In 424, Kou took these texts with him to the Wei court.There, he was welcomed by Emperor Taiwu and garnered the support of Cui Hao, the prime minister.