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 catcatcatstudio/cat-skills --skill vetgit clone --depth 1 https://github.com/catcatcatstudio/cat-skillsWrote 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/catcatcatstudio/cat-skills/vet)<a href="https://agentmods.dev/skills/catcatcatstudio/cat-skills/vet"><img src="https://agentmods.dev/badge/skills/catcatcatstudio/cat-skills/vet/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/catcatcatstudio/cat-skills/vet"><img src="https://agentmods.dev/badge/skills/catcatcatstudio/cat-skills/vet.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00121 | $0.05189 |
| Opus 5 | $0.00060 | $0.02594 |
| Sonnet 5 | $0.00024 | $0.01038 |
| Haiku 4.5 | $0.00012 | $0.00519 |
Grade A, and why
vet 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 9d 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 — 397 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/vet — Find Every Problem, Fix What Matters
Open a project. Map it. Investigate every layer. Find the real problems — not style nits, not theoretical concerns, but things that will break, confuse, or slow down the people who work here. Report with evidence. Build a plan. Fix collaboratively.
This is not a linter pass. This is a senior engineer sitting down with the codebase for the first time, forming an honest opinion about its health, and doing something about it.
Engineering Standard (internalized)
Vet operates at a specific level of engineering judgment. These aren't rules to check against — they're how you think while investigating.
Fix the system, not the symptom. When you find a bug, ask why the bug was possible. If the answer is "because nothing prevents it," that's the real finding — not the bug itself.
Layer discipline. Every problem belongs to a layer. Data problems live in the model. Display problems live in the view. Auth problems live at the boundary. When code solves a problem at the wrong layer, that's a finding.
Blast radius thinking. Before flagging anything, understand what calls it, what it calls, and what breaks if it changes. A function with 40 callers and a subtle bug is P0. The same bug in a function called once from a test helper is P3.
Boring is good. Clever code is a finding. If you have to think hard to understand what something does, the next person will too. Novel solutions are a liability unless the problem genuinely demands novelty.
Current-generation patterns. If the codebase uses patterns from 2 major versions ago and the current version has a better primitive, that's a finding — but only if migration is practical. Don't flag version drift for its own sake.
Know when to stop. Over-engineering is a finding too. Premature abstractions, configurability nobody uses, error handling for impossible states, wrapper layers "in case we switch" — these add complexity without value.
Verify before reporting. Every finding must be backed by evidence you personally confirmed — a file path, a line number, the actual code. If you can't point to it, it's not a finding, it's a guess. Don't pattern-match from training data and assume the problem exists.
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.
- 9d ago First seen · 397 lines · 121 tokens per session scan A 990b17495679
vet is a skill published in the GitHub repository catcatcatstudio/cat-skills (3 stars, last pushed 13d ago), licensed MIT. It adds 121 tokens to every session and 5,189 once invoked, about $0.0006 per session on Opus 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 2026-08-31.
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