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 HoangNguyen0403/agent-skills-standard --skill system-design-reviewgit clone --depth 1 https://github.com/HoangNguyen0403/agent-skills-standardWrote 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/hoangnguyen0403/agent-skills-standard/system-design-review)<a href="https://agentmods.dev/skills/hoangnguyen0403/agent-skills-standard/system-design-review"><img src="https://agentmods.dev/badge/skills/hoangnguyen0403/agent-skills-standard/system-design-review/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/hoangnguyen0403/agent-skills-standard/system-design-review"><img src="https://agentmods.dev/badge/skills/hoangnguyen0403/agent-skills-standard/system-design-review.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00055 | $0.01538 |
| Opus 5.5 | $0.00022 | $0.00615 |
| Sonnet 5.5 | $0.00011 | $0.00308 |
| Haiku 4.5 | $0.00006 | $0.00154 |
Grade A, and why
system-design-review 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 6d 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 — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.
System Design Review
Priority: P1 (HIGH)
Score claims against evidence appropriate to the declared review scope. A proposed design may support a design-readiness verdict through stated mechanisms and planned validation; it cannot claim operational readiness from plans alone. An implementation review requires implementation evidence; an operations claim requires production runtime/deployment evidence.
Nine Axes (score each applicable axis 0-10)
| Axis | Scores 10 when | Scores 0 when |
|---|---|---|
| Requirements | Functional, NFR, and out-of-scope written with owners | Only a feature description exists |
| Capacity evidence | Peak QPS, storage, and bandwidth computed and current | Numbers absent or older than the last traffic change |
| Redundancy | Failure domains, recovery mechanisms and ownership fit the stated objective; proposals include validation criteria, operations claims require measured drills when recovery is in scope | Critical SPOF or no viable recovery for the stated objective |
| Data scaling | Access patterns mapped, ownership single, growth path stated; critical-flow authority, derived copies, freshness, and backlog are checked when material | One shared store, no growth plan, unbounded tables, or a material flow invariant/copy risk left unresolved |
| Caching | Hot read paths cached with TTL and invalidation defined | No cache on a proven hot path, or uninvalidatable cache |
| Async offload | Slow/bursty work is isolated when required by stated SLO or failure constraints, with bounded drain/recovery; bounded synchronous work is valid when it meets them | Required isolation is absent or synchronous coupling violates the stated constraints |
| Observability | Journey indicators, signal/alert ownership, runbooks and validation fit declared scope; operations claims require observed SLO/telemetry | No relevant journey signals, owner or response path for a material risk |
| Rollout | Canary or flag with metric rollback trigger and reversible migrations | Big-bang deploy, irreversible migration |
| Cost proportionality | Spend is sized to the traffic and the risk, and someone can state it | Topology bought for an imagined scale nobody measured |
What ships with it
4 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.
- 6d ago Changed · +12 lines 2ea78f997d33
- 19d ago Changed d7917424a183
- 1mo ago Changed · +13 lines 82896c25340b
- 1mo ago Changed ff35ab4ca3ed
- 1mo ago First seen · 69 lines · 55 tokens per session scan A c7b824bff9dc
system-design-review is a skill published in the GitHub repository HoangNguyen0403/agent-skills-standard (583 stars, last pushed today), licensed MIT. It adds 55 tokens to every session and 1,538 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 2026-08-30.
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