What was long john silver hired for in Treasure Island?

In "Treasure Island" by Robert Louis Stevenson, Long John Silver is initially hired as the ship's cook for the voyage aboard the Hispaniola. However, he is later revealed to be a cunning pirate and the leader of a mutiny, seeking to reclaim buried treasure for himself. His charisma and manipulative nature make him a central figure in the story, blurring the lines between ally and adversary.