BUKHARI 2692: from Ummah Um Kulthūm b. ʿUqbah —
That she heard Messenger of Allah ﷺ saying, "He who makes peace between the people by inventing good information or saying good things, is not a liar."

البخاري ٢٦٩٢: عن امه ام كلتهوم بن عقبه —
أَخْبَرَهُ أَنَّ أُمَّهُ أُمَّ كُلْثُومٍ بِنْتَ عُقْبَةَ أَخْبَرَتْهُ أَنَّهَا سَمِعَتْ رَسُولَ اللَّهِ ﷺ يَقُولُ لَيْسَ الْكَذَّابُ الَّذِي يُصْلِحُ بَيْنَ النَّاسِ فَيَنْمِي خَيْرًا أَوْ يَقُولُ خَيْرًا


Agreed Upon (Luʿluʿ wa-al-Marjān)
Bukhārī > Peacemaking > § He who makes peace between the people is not a liar
hadithunlocked.com