Parleying with Monsters
Source: Tasha’s Cauldron of Everything p. 148
A quote from Tasha
Why fight if a lively chat is possible? If things get out of hand, just show yourself out with a dimension door.
Meeting a monster doesn’t have to spark a fight. An offering, like food, can calm some hostile monsters, and sapient creatures often prefer to talk than to draw weapons. If the adventurers try to parley with a monster, you may improvise the encounter or use the “social interaction rules” in the “Dungeon Master’s Guide”. Consider granting the characters advantage on any ability check they make to communicate with a creature if they offer something it wants. The “Monsters’ Desires” section below suggest things that a creature might like, depending on its type.
Monster Research
Adventurers can research what a creature is likely to desire. The Monster Research table suggests which skills can be used to learn about a creature of a particular type. The DC for a relevant ability check equals 10 + the creature’s challenge rating.