The article The Knife Catcher at the Head of the Bed writes about Cao Cao s character

Cao Cao was a suspicious man. He is also a traitor. His servant saw that the building where he slept was outside, and turned it into order for him. Cao Cao thought he was going to kill him, so he took up a knife and killed him. And said to the outside world that he killed someone in his dream, but in fact he was suspicious.

This allusion comes from the "New Language of the World, Rongzhi" organized by Liu Yiqing of the Southern Dynasty >>>More

is too suspicious, and wants to use talents for his own use, but at the same time, he is also guarding against villains. >>>More

The reason why Cao Cao wanted to send someone to hunt down this envoy was because the envoy's vision was unique, which proved that he had real talent and learning, and Cao Cao was afraid that this person would be unfavorable to him after returning to the Xiongnu. At the same time, he was also afraid that the Xiongnu envoys would say unfavorable things to him after returning to the Xiongnu. >>>More

Because Cao Cao felt that the envoy had seen through his plan, he must be a very wise person, and since he could not take it for his own use, he would kill the envoy so that no one else could use him.