VSCode custom command question

Can't understand how I can run custom command with VS Code.
Try add this to tasks.json, but It doesn't work.

{
  "type": "shell",
  "task": "Monitor 115200",
    "command": "platformio",
    "args": [
        "--baud", "115200",
        "--port", "/dev/cu.wchusbserial1420",
    ],
  "problemMatcher": [
    "$platformio"
  ],
  "label": "PlatformIO: Monitor 115200"
}

Executing task: platformio --baud 115200 --port /dev/cu.wchusbserial1420 <
/bin/bash: platformio: command not found
Не удалось запустить процесс терминала "/bin/bash '-c', 'platformio --baud 115200 --port /dev/cu.wchusbserial1420'" (код выхода: 127).

pio also doesn't work.

Start with the VS Code tasks.json example and the reported command output showing that platformio and pio cannot be found. Reproduce the custom task setup, then update the documentation to explain the supported command and required environment so the task runs successfully.