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 vasilyu1983/AI-Agents-public --skill software-security-appsecgit clone --depth 1 https://github.com/vasilyu1983/AI-Agents-publicWrote 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/vasilyu1983/ai-agents-public/software-security-appsec)<a href="https://agentmods.dev/skills/vasilyu1983/ai-agents-public/software-security-appsec"><img src="https://agentmods.dev/badge/skills/vasilyu1983/ai-agents-public/software-security-appsec/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/vasilyu1983/ai-agents-public/software-security-appsec"><img src="https://agentmods.dev/badge/skills/vasilyu1983/ai-agents-public/software-security-appsec.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
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 →
- medium Excessive Agency · line 207 Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
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 | $0.00031 | $0.03434 |
| Opus 5 | $0.00015 | $0.01717 |
| Sonnet 5 | $0.00006 | $0.00687 |
| Haiku 4.5 | $0.00003 | $0.00343 |
Grade A, and why
software-security-appsec 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 — 238 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Software Security And AppSec
Use this skill for application-layer security: authentication, authorization, input and output handling, cryptography, supply-chain controls, API security, threat modeling, and security reviews. It is the AppSec decision layer, not general backend or infrastructure hardening.
Quick Reference
| Task | Use |
|---|---|
| Auth and authorization choices | references/authentication-authorization.md, assets/web-application/template-authentication.md, assets/web-application/template-authorization.md |
| Input handling, uploads, rendering, and common bugs | references/input-validation.md, references/common-vulnerabilities.md |
| Secure design and threat modeling | references/secure-design-principles.md, references/threat-modeling-guide.md |
| API and supply-chain security | references/api-security-patterns.md, references/supply-chain-security.md, assets/api/template-secure-api.md |
| Crypto and transport choices | references/cryptography-standards.md |
| Secret-storage selection | See "Secret-Storage Selection" below — choosing encrypted vs plaintext at the provider, and how to verify after storing |
| Incident response and security program framing | references/incident-response-playbook.md, references/security-business-value.md, references/operational-playbook.md |
Secret-Storage Selection
Every major cloud provider has two surface-similar storage classes: one encrypted-at-rest with no readback, one plaintext-visible in the dashboard. Picking the wrong one is silent — the app still works — and the audit log for who-read-what exists only on the encrypted form. Plaintext reads are invisible.
What ships with it
28 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- agents/openai.yaml 339 B
- assets/api/template-secure-api.md 19 KB
- assets/cloud-native/crypto-security.md 11 KB
- assets/mobile/template-mobile-security.md 24 KB
- assets/web-application/template-authentication.md 15 KB
- assets/web-application/template-authorization.md 21 KB
- data/sources.json 23 KB
- evals/evals.json 8.7 KB
- learnings.consolidated.md 600 B
- learnings.md 386 B
- references/advanced-xss-techniques.md 22 KB
- references/api-security-patterns.md 23 KB
- references/authentication-authorization.md 8.5 KB
- references/common-vulnerabilities.md 24 KB
- references/cryptography-standards.md 21 KB
- references/dotnet-efcore-crypto-security.md 3.9 KB
- references/game-theory-applied.md 22 KB
- references/incident-response-playbook.md 22 KB
- references/input-validation.md 27 KB
- references/operational-playbook.md 18 KB
- references/owasp-top-10.md 22 KB
- references/reliability-theory-applied.md 48 KB
- references/secure-design-principles.md 16 KB
- references/security-business-value.md 14 KB
- references/smart-contract-security-auditing.md 15 KB
- references/supply-chain-security.md 6.9 KB
- references/threat-modeling-guide.md 27 KB
- references/zero-trust-architecture.md 4.3 KB
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 · 238 lines · 31 tokens per session scan A 5f773de88fc4
software-security-appsec is a skill published in the GitHub repository vasilyu1983/AI-Agents-public (87 stars, last pushed 10d ago), licensed MIT. It adds 31 tokens to every session and 3,434 once invoked, about $0.0002 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 2026-09-03.
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