pub fn list_messages(
  token: String,
  user_id: String,
) -> Effect(List(Message))

pub fn list_messages_request(
  token: String,
  user_id: String,
) -> Request(BitArray)

pub fn list_messages_response(
  response: Response(BitArray),
) -> Result(List(Message), Snag)

pub fn send(
  token: String,
  from: String,
  to: String,
  message: String,
) -> Effect(Message)

pub fn send_request(
  token: String,
  from: String,
  to: String,
  message: String,
) -> Request(BitArray)

pub fn send_response(
  response: Response(BitArray),
) -> Result(Message, Snag)