I want to know the answer to the following question:
When did Yongle Emperor send Yang Sanbao into Tibet?
All the background I'm provided with is that "Shih-Shan Henry Tsai writes that the Yongle Emperor sent his eunuch Yang Sanbao into Tibet in 1413 to gain the allegiance of various Tibetan princes, while the Yongle Emperor paid a small fortune in return gifts for tributes in order to maintain the loyalty of neighboring vassal states such as Nepal and Tibet.". Is that enough to answer the question?