Alchemy.Client.delete_reaction

You're seeing just the function delete_reaction, go back to Alchemy.Client module for more information.
Link to this function

delete_reaction(message, emoji, user)

Specs

delete_reaction(
  Alchemy.Message.t() | {channel_id(), message_id()},
  unicode() | Alchemy.Reaction.Emoji.t(),
  snowflake() | Alchemy.User.t()
) :: {:ok, nil} | {:error, term()}

Deletes a reaction added by another user.

Requires the MANAGE_MESSAGES permission.