Skill inventory

Make the skill-inventory utility available to this agent and hand off to its own documentation. This skill and the utility share a name: the utility is an offline Python tool that ships as an armory utility package, which the Skills CLI and the Claude Code plugin marketplace do not install. This skill is the installable entry point that bridges that gap, without copying the utility's code or measurement rules.

When to use

Triggers group into inventory audits ("audit my skill inventory", "find unused skills", "which skills were read?"), cost questions ("how much do skill descriptions cost?") and setup ("set up skill-inventory", "run the skill inventory utility").

Prerequisites

macOS or Linux with bash, curl, unzip, shasum or sha256sum, Python 3.12+ and uv. Installing needs network access to GitHub once; measurement afterwards runs offline.

Workflow

1. Locate an existing install. Run scripts/ensure-utility.sh from this skill's directory. It checks ~/.claude/utilities/skill-inventory (the armory profile installer's location) and ${XDG_DATA_HOME:-~/.local/share}/armory/utilities/skill-inventory. Exit 0 prints UTILITY_ROOT= and VERSION=; exit 3 means it is not installed.
2. On exit 3, ask the owner before installing. Installing downloads and later runs code from the armory rolling latest release. With approval, run scripts/ensure-utility.sh --install, or --install DEST for another location outside every Git repository; a relative DEST is resolved against the current directory.
3. Export the printed root: export UTILITY_ROOT=....
4. Bootstrap the pinned dependency once: uv run --no-project --script "$UTILITY_ROOT/scripts/skill_inventory.py" --help.
5. Read the utility's UTILITY.md and its operator guide (operator-guide.md in the utility's references folder), then follow them. They own the commands, private output rules, approval gates and interpretation of results; this skill does not restate them.
6. Start with the read-only measure --aggregate-only run the guide describes. recommend writes only a private proposal. archive and restore --apply move files and need the owner's separate, explicit authorization.

Install behavior

ensure-utility.sh --install does the following, and stops with nothing installed if any step fails:

1. Downloads checksums.txt from the armory latest release and finds exactly one skill-inventory-X.Y.Z.utility entry.
2. Downloads that archive and compares its SHA-256 with the listed value.
3. Unpacks it into a hidden temporary directory beside the destination and checks it contains UTILITY.md and scripts/skill_inventory.py.
4. Renames it to the destination only if nothing exists there, so an interrupted install never leaves a partial copy in place.

The checksum guards against a corrupted or truncated download. It comes from the same release, so it does not prove who published the archive.

The script never upgrades or overwrites an existing install. To upgrade, have the owner compare the installed VERSION with the release, move the old directory aside, then install again.

Worked example

SKILL_DIR="$HOME/.claude/skills/skill-inventory"      # where this skill was installed
"$SKILL_DIR/scripts/ensure-utility.sh"                    # exit 3: not installed
# Owner approves the download.
"$SKILL_DIR/scripts/ensure-utility.sh" --install
# UTILITY_ROOT=$HOME/.local/share/armory/utilities/skill-inventory (expanded)
# VERSION=1.0.0
export UTILITY_ROOT="$HOME/.local/share/armory/utilities/skill-inventory"
uv run --no-project --script "$UTILITY_ROOT/scripts/skill_inventory.py" --help
# Next: follow $UTILITY_ROOT/references/operator-guide.md for the measure run.

Output

Report the utility root and version, whether anything was installed, and then the utility's own output as its guide describes. Stdout from the utility is anonymous aggregate JSON; exit 2 means incomplete or refused, not an empty result.

Troubleshooting

Files