@type t() :: %OpenCode.Generated.StepFinishPart{
  cost: number(),
  id: String.t(),
  message_id: String.t(),
  reason: String.t(),
  session_id: String.t(),
  snapshot: String.t() | nil,
  tokens: OpenCode.Generated.StepFinishPartTokens.t(),
  type: String.t()
}