The Messenger of Allah ﷺ said, "I was sent only to perfect noble character."
حدثنا سعيد بن منصور قال حدثنا عبد العزيز بن محمد عن محمد بن عجلان عن القعقاع بن حكيم عن أبي صالح
قال رسول الله ﷺ إنما بعثت لأتمم صالح الأخلاق
Its chain of transmission is sahih. Hakim also related it in Mustadrak 2/613, saying it meets the criteria of both Bukhari and Muslim, and Dhahabi agreed with him. Iraqi also graded it sahih in his commentary on Ihya 2/155, attributing it to Ahmad and grading it sahih.