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 Zephyrex21/claude-skills-vetted --skill system-designgit clone --depth 1 https://github.com/Zephyrex21/claude-skills-vettedWrote 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/zephyrex21/claude-skills-vetted/system-design)<a href="https://agentmods.dev/skills/zephyrex21/claude-skills-vetted/system-design"><img src="https://agentmods.dev/badge/skills/zephyrex21/claude-skills-vetted/system-design/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/zephyrex21/claude-skills-vetted/system-design"><img src="https://agentmods.dev/badge/skills/zephyrex21/claude-skills-vetted/system-design.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 | $0.00120 | $0.00511 |
| Opus 5 | $0.00060 | $0.00255 |
| Sonnet 5 | $0.00024 | $0.00102 |
| Haiku 4.5 | $0.00012 | $0.00051 |
Grade A, and why
system-design 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 12d 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
A licence we could not identify
The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.
What ships with it
2 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.
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.
- 12d ago First seen · 50 lines · 120 tokens per session scan A 3acde4aa14f9
system-design is a skill published in the GitHub repository Zephyrex21/claude-skills-vetted (2 stars, last pushed 1mo ago), with no licence file. It adds 120 tokens to every session and 511 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.
Other skills, from other repositories
offensive-api-abuse
Advanced API exploitation methodology focused on business logic abuse and sophisticated attack patterns that bypass traditional security controls. Covers business logic bypass through API call chaining and workflow manipulation. Addresses GraphQL-specific attacks including batching for credential brute-force, query…
offensive-graphql
Offensive methodology for attacking GraphQL APIs during penetration tests and bug bounty engagements. Covers the full attack lifecycle: endpoint discovery, introspection abuse and blind schema reconstruction when introspection is disabled, authentication and authorization bypass through Relay node IDs and nested…
DelphiMVCFramework
Patterns for development with DelphiMVCFramework (DMVC) — controllers, Active Record, JWT, Swagger.
Horse Framework
Patterns for developing REST APIs with Horse framework in Delphi.
Dext Framework Patterns
Architectural patterns, Entity ORM, Minimal APIs and dependency injection for projects created with Dext Framework (cesarliws/dext).
csharp-api-controller-standards
Defines the coding standards, patterns, and conventions for ASP.NET Core REST API controllers. Rules cover routing, HTTP verbs, response types, XML documentation, dependency injection, and asynchronous execution. Apply these rules uniformly to ensure a consistent, predictable, and well-documented API surface.