---
name: cardputer-buddy
description: Iterate on the Cardputer-Adv MicroPython app bundle (Claude Buddy, Snake, Hello) after the device is already provisioned via m5-onboard. Use when the user wants to add a new app, push a single changed .py without re-flashing, watch device serial logs, or run a one-shot REPL command. Trigger on "add an app", "push to the cardputer", "tail the device", "run on the device", or follow-up work after /start-making.
---

# Cardputer Buddy app bundle

The `buddy/` directory in the local `build-with-claude` clone is the MicroPython payload that `m5-onboard` installs onto `/flash/`. Work inside that clone.

## Device layout

```
/flash/
├── main.py              launcher menu (replaces UIFlow's boot flow)
├── buddy_*.py           shared libs (BLE, UI, state, protocol, chars)
├── burst_frames.py      sprite frames
└── apps/
    ├── claude_buddy.py  BLE client → Claude Desktop's Hardware Buddy
    ├── hello_cardputer.py
    └── snake.py
```

`main.py` scans `/flash/apps/` at boot and lists every `.py` as a menu entry. Drop a file into `buddy/device/apps/`, push it, and it appears on next boot.

## Adding an app

Crib from `buddy/device/apps/hello_cardputer.py` — smallest example of keyboard polling, font, and exit conventions. Then push without re-flashing:

```bash
python3 onboard/scripts/install_apps.py --port <PORT> --src buddy
```

`<PORT>` is whatever `detect.py` reported last run (e.g. `/dev/cu.usbmodem1101`, `/dev/ttyACM0`, `COM3`).

## Dev loop tooling (`buddy/scripts/`)

```bash
# Push a subset of files over USB-serial
python3 buddy/scripts/push.py --port <PORT> --files apps/snake.py

# Watch device logs
python3 buddy/scripts/tail_serial.py --port <PORT>

# One-shot REPL exec
python3 buddy/scripts/repl_run.py --port <PORT> --script "import os; print(os.listdir('/flash'))"
```