example rule for opening iTerm2 with command+shift+t with Karabiner Elements

karabiner_launch_apps.json

# https://karabiner-elements.pqrs.org/docs/json/location/

{
  "title": "Launch apps",
  "rules": [
    {
      "description": "Launch iTerm with command + shift + t",
      "manipulators": [
            {
                "from": {
                    "key_code": "t",
                    "modifiers": {
                        "mandatory": [
                            "left_command",
                            "left_shift"
                        ],
                        "optional": [
                            "caps_lock"
                        ]
                    }
                },
                "to": [
                    {
                        "shell_command": "open '/Applications/iTerm.app'"
                    }
                ],
                "type": "basic"
            }
        ]
    }
  ]
}