inspect-machine

Inspect the machine

When to use

• You are about to plan or test something whose feasibility depends on hardware: a local model or GPU work, vision or audio features, a USB or serial device, heavy parallel builds.
• A task says "on this machine", "use the camera / mic / GPU", or a test fails in a way that smells like missing hardware.
• Once per session at most. Re-run only if the user plugs something in or asks.

Don't use it for ordinary coding work. Most tasks don't care what the machine is.

Rules

1. List, never use. These commands only read the system's device lists. Never open a camera or microphone, capture anything, write to a device, or start a Bluetooth scan.
2. Ask before using a device. Knowing a camera exists is not permission to use it. Ask the user (ask_user) before any step that opens a device, and say what for. The operating system may ask too. When there is no one to ask (CI, piped or -p mode, any run where ask_user is unavailable or unanswered), never use a device: report what you found and stop there.
3. Nothing identifying in what you keep. Drop serial numbers, MAC and Bluetooth addresses, UUIDs and unique ids, device and host names (e.g. "Alex's AirPods"), and user names. Keep class, model, vendor, capability and counts.
4. Don't commit it. The profile describes one machine at one moment. Keep it in this session's context. Never write it to memory/, the journal, an issue or a commit.

Quick reference

Start with uname -s. Each command may be missing: skip what fails, and don't install anything to fill a gap.

macOS and Linux: cores, disk (Windows gets these from its own block)

getconf _NPROCESSORS_ONLN 2>/dev/null; df -h . | tail -1

macOS (system_profiler takes a few seconds; one call for all types)

sysctl -n machdep.cpu.brand_string hw.memsize hw.ncpu
hw=$(mktemp)   # private temp file; removed after the strip step below
system_profiler -json SPDisplaysDataType SPCameraDataType SPAudioDataType SPUSBDataType 2>/dev/null > "$hw"

Apple silicon has a Neural Engine: the chip model in machdep.cpu.brand_string (e.g. "Apple M3") tells you. Its GPU shares system memory, so there is no separate VRAM figure: say "unified, N GB" rather than "unknown".