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 SebastienDegodez/skraft-plugin --skill mutation-testinggit clone --depth 1 https://github.com/SebastienDegodez/skraft-pluginWrote 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/sebastiendegodez/skraft-plugin/mutation-testing)<a href="https://agentmods.dev/skills/sebastiendegodez/skraft-plugin/mutation-testing"><img src="https://agentmods.dev/badge/skills/sebastiendegodez/skraft-plugin/mutation-testing/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/sebastiendegodez/skraft-plugin/mutation-testing"><img src="https://agentmods.dev/badge/skills/sebastiendegodez/skraft-plugin/mutation-testing.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 | $0.00060 | $0.01606 |
| Opus 5.5 | $0.00024 | $0.00642 |
| Sonnet 5.5 | $0.00012 | $0.00321 |
| Haiku 4.5 | $0.00006 | $0.00161 |
Grade A, and why
mutation-testing 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 7d 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.
The source is not reproduced here
Licensed GPL-3.0
The repository is licensed GPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
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.
- 7d ago Changed 83a9a97eccf7
- 9d ago Changed · +10 lines · +12 tokens per session a47f742824af
- 10d ago Changed · +9 lines · +4 tokens per session dc8219cc2ed6
- 16d ago Changed · +1 lines 0d29e7008d91
- 23d ago Changed · -74 lines · +9 tokens per session 2d0fe6e9a78e
- 1mo ago First seen · 206 lines · 35 tokens per session scan A 1f73bda68a92
mutation-testing is a skill published in the GitHub repository SebastienDegodez/skraft-plugin (12 stars, last pushed today), licensed GPL-3.0. It adds 60 tokens to every session and 1,606 once invoked, about $0.0002 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 2026-09-03.
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