Guo Ziyi
Notwithstanding these projects, one of the agendas that Emperor Dezong had early in his reign was peace with Tufan, and he ordered a general release of Tufan captives. He also sent the official Wei Lun () as an emissary to Tufan. When Wei requested that Emperor Dezong personally sign a letter offering peace addressed to the king of Tufan, Yang believed that this would overly dignify the Tufan king, and therefore requested that the senior general Guo Ziyi sign the letter, with Emperor Dezong writing, "approved," on the letter. Emperor Dezong agreed.