Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add joshukraine/dotfiles --skill ruby-gcgit clone --depth 1 https://github.com/joshukraine/dotfilesWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/joshukraine/dotfiles/ruby-gc)<a href="https://agentmods.dev/skills/joshukraine/dotfiles/ruby-gc"><img src="https://agentmods.dev/badge/skills/joshukraine/dotfiles/ruby-gc/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/joshukraine/dotfiles/ruby-gc"><img src="https://agentmods.dev/badge/skills/joshukraine/dotfiles/ruby-gc.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00025 | $0.02454 |
| Opus 5.5 | $0.00010 | $0.00982 |
| Sonnet 5.5 | $0.00005 | $0.00491 |
| Haiku 4.5 | $0.00003 | $0.00245 |
Grade A, and why
ruby-gc scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 153 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Ruby GC
Garbage-collect asdf-installed Ruby versions that nothing on the system references.
Dry-run by default. Without --apply, this is a read-only report and you must not uninstall anything.
Arguments
$ARGUMENTS— pass--applyto enable the uninstall step. Absent that flag, stop after the report.--applyenables deletion; it does not authorize it. You still show the full table and get an explicit yes first.
Safety rules
These are non-negotiable. The cost of a wrong delete is a broken app plus a slow rebuild; the cost of a wrong keep is a few hundred MB.
- Never delete the global version — the one in
~/.tool-versions. - Never delete a version that has any pin on disk, wherever that pin lives.
- Never delete without showing the table and getting an explicit confirmation in the same session.
- If the scan errors, or returns implausibly few pins, STOP and report. A truncated scan is indistinguishable from "nothing uses this" — it produces a confident delete list that breaks real apps. This has happened; treat a thin result as a bug in the scan, not a licence to delete. "Implausibly few" is measured against the July 2026 baseline in "Calibration" below — check it every run, before classifying anything.
- Uninstall one version at a time, reporting each result before the next.
Your task
1. Inventory what's installed
asdf list ruby
du -sh ~/.asdf/installs/ruby/*
2. Read the global pin
cat ~/.tool-versions
This is a symlink into ~/dotfiles/asdf/.tool-versions (the real dotfiles). Note that ~/code/my_repos/dotfiles/ and ~/dotfiles.bak/ are stale clones carrying outdated pins — ignore them as authorities on the global version, though their pins still count under rule 2 until the user cleans them up.
3. Scan for pins — FULL DEPTH
find ~ -type f \( -name .tool-versions -o -name .ruby-version \) \
-not -path '*/node_modules/*' -not -path '*/.git/*' \
-not -path '*/Library/*' -not -path '*/.Trash/*' \
-not -path '*/vendor/*' -not -path '*/.asdf/*' \
-not -path '*/.local/share/nvim/*' -not -path '*/.local/share/zap/*' \
-not -path '*/.local/share/neobean/*' \
-exec grep -H . {} + 2>/dev/null
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago First seen · 153 lines · 25 tokens per session scan A 162ebefca600
ruby-gc is a skill published in the GitHub repository joshukraine/dotfiles (429 stars, last pushed 5d ago), licensed MIT. It adds 25 tokens to every session and 2,454 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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