Borrowing it
Nothing to install: this file belongs to moberghr/mtk-agent-toolkit. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/moberghr/mtk-agent-toolkit/main/.claude/skills/security-and-hardening/SKILL.mdgit clone --depth 1 https://github.com/moberghr/mtk-agent-toolkitWrote 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/moberghr/mtk-agent-toolkit/security-and-hardening)<a href="https://agentmods.dev/skills/moberghr/mtk-agent-toolkit/security-and-hardening"><img src="https://agentmods.dev/badge/skills/moberghr/mtk-agent-toolkit/security-and-hardening/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/moberghr/mtk-agent-toolkit/security-and-hardening"><img src="https://agentmods.dev/badge/skills/moberghr/mtk-agent-toolkit/security-and-hardening.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Agent Snooping · line 23 Skill reads from agent configuration directories (.claude/, .codex/, .gemini/). These directories may contain API keys, personal settings, and other credentials that the skill has no legitimate need to access.Fix: Remove all code or instructions that access agent configuration directories (.claude/, .codex/, .gemini/). If configuration values are needed, pass them explicitly as parameters or environment variabl
- medium Agent Snooping · line 68 Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
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 | $0.00037 | $0.00680 |
| Opus 5.5 | $0.00015 | $0.00272 |
| Sonnet 5.5 | $0.00007 | $0.00136 |
| Haiku 4.5 | $0.00004 | $0.00068 |
Grade A, and why
security-and-hardening scanned grade A with 1 finding 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 16d 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.
Reads agent configuration directorieslowAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
cat .claude/tech-stack 2>/dev/null || echo "(not set)" Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.
How it starts
The opening of the file, as written. The whole thing — 69 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Security And Hardening
Active Stack
echo "--- Tech Stack ---"
cat .claude/tech-stack 2>/dev/null || echo "(not set)"
Overview
Treat security and compliance as design constraints, not final review polish. Changes to serious software must preserve confidentiality, integrity, auditability, and least privilege.
When To Use
- Auth or authorization changes; secrets or configuration changes
- Audited state mutations (e.g. financial state, patient records, legal documents — see domain supplement)
- New endpoints, external integrations, infrastructure, or IAM changes
When NOT To Use
- Purely internal non-sensitive refactors with no new data flow or boundary change
Workflow
- Read the domain and security supplement (
.claude/references/domain-finance.md, or the team'sdomain-<name>.md) for regulated state, sensitive data, audit invariants and review questions. - Read the stack skill's
## Framework Patternsfor framework-level auth and validation idioms. - Identify trust boundaries:
- user input
- external service input
- internal privileged operations
- Check auth and authorization requirements.
- Check PII, secrets, and logging behavior.
- Check audit requirements for state changes that require an audit trail.
- Check query safety, transaction boundaries, and error exposure.
- For infra, check least privilege, blast radius, and secret access scope.
- Supply chain — dependency intake. If the diff adds or replaces a third-party dep (any of
package.json,*.csproj,Directory.Packages.props,requirements.txt,pyproject.toml,Pipfile,go.mod,Cargo.toml,Gemfile,composer.json), walk the new dep through.claude/references/dependency-intake-checklist.md— scope, maintenance, size, security, license. TwoPoorratings block; onePoorrequires written override. Cite concrete evidence (CVE id, last-release date, license SPDX) per Poor rating. - If a requirement is unclear, stop and ask rather than guessing.
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.
- 16d ago Changed · -14 lines f9020719d5eb
- 1mo ago Changed · -2 lines e1482f123c23
- 2mo ago First seen · 85 lines · 37 tokens per session scan A f45fce22cd0e
security-and-hardening is a skill published in the GitHub repository moberghr/mtk-agent-toolkit (9 stars, last pushed 8d ago), licensed MIT. It adds 37 tokens to every session and 680 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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