Check tools

Agents should not scrape df -h, free -h, or uptime. Those commands are for a human looking at a terminal. The numbers are in the right columns if you already know the format, and in the wrong ones if you are guessing.

machina prints small tables. The same binary answers to the short names in ~/.local/bin.

Command	What it prints
`disk`	real filesystems: device, size, used, avail, use%, mount
`mem`	total, used, available, swap
`load`	1/5/15 minute load, cpu count
`home-map`	top-level home entries that machina knows, plus whether `AGENTS.md` is there
`machina where PATH`	which work dir a path belongs in

disk warns on any filesystem at 90% full or above. It skips tmpfs, proc, sysfs, cgroup, and other virtual mounts. Pass -a to see those too.

home-map does not compute directory sizes by default. Walking ~/src can take minutes. Pass -s if you need sizes.

Output rules

ASCII. No color, no progress bars, no emoji.
Stable column names so an agent can quote a line back.
One filesystem or one fact per line.
Exit 0 on success, 1 if the report itself failed, 2 on usage error. A full disk is still exit 0; the warn line is the signal.

Why these four

Disk is how agents notice they are about to write a dataset onto a 46G root. Memory is how they notice a runaway compile. Load is how they notice the box is already busy. The home map is how they stop asking where things go.

More tools can be added the same way: a function in report.go, a name in binLinks. If the output needs a library to parse, the command is the wrong shape.