Is “What was Jian Shu's reputation before he served in Qin?” true?

In the 'Records of the Grand Historian: Annals of Qin', through the mouth of Baili Xi, his great talent hidden from the world is revealed: 'Baili Xi declined, saying: "I am not as good as my friend Jian Shu; Jian Shu is virtuous but the world does not know him."' The 'Chronicles of the Eastern Zhou Kingdoms', chapter 45, also confirms his unshakable position as a strategist in Qin: 'It is said that the commander of the central army, Xian Zhen, already knew of Qin's plan to attack Zheng, and came to see Duke Xiang, saying: "Qin disregarded the remonstrances of Jian Shu and Baili Xi, and attacked Zheng from a thousand li away."'