qmk_firmware/keyboards/atset/at3/info.json

{
  "keyboard_name": "AT3",
  "maintainer": "atset",
  "layouts": {
    "LAYOUT": {
      "layout": [{"label":"k00", "x":0, "y":0}, {"label":"k01", "x":1, "y":0}, {"label":"k02", "x":2, "y":0}]
    }
  }
}