@type t() :: %Pi.Protocol.Session.Snapshot{
  completed_at: String.t() | nil,
  current: String.t() | nil,
  current_started_at: String.t() | nil,
  duration_ms: non_neg_integer() | nil,
  error: String.t() | nil,
  events: [Pi.Protocol.Session.Event.t()],
  id: String.t(),
  last_activity_at: String.t() | nil,
  latest: String.t() | nil,
  message_count: non_neg_integer(),
  name: String.t() | nil,
  parent_id: String.t() | nil,
  prompt: String.t() | nil,
  recent_output: [String.t()],
  response: String.t() | nil,
  result: term(),
  run_count: non_neg_integer(),
  started_at: String.t() | nil,
  status: String.t(),
  turn_count: non_neg_integer(),
  updated_at: String.t() | nil,
  usage: map() | nil
}