› GPT-6.1 Terra has six reasoning levels: none, low, medium, high, xhigh and max.
› I tested what each level delivers and what it costs using the same six difficult tasks with one correct answer: Sudoku, a logic puzzle, PIN-code counting, a loan payment, working days and letter counting.
› I also tested a technical drawing and a letter to a tax authority.
› With reasoning set to none, Terra solved one of the six tasks.