software-design-system-design

software-design-system-design is a skill for Claude Code, Codex from xiaohei-info/oh-my-multica. It costs 119 tokens per session (4,108 once invoked), scanned A, original, MIT.

A structured method for designing and reviewing distributed systems: software made of multiple services or machines that work together. It covers requirements, high-level structure, capacity estimates, and common building blocks such as load balancers, caches, queues, and databases.

In plain words
What is it for?
Use it for system-design interviews, capacity planning, service architecture, and designs involving scaling, high availability, rate limiting, caching, databases, or message queues.
Why use it?
It reduces the risk of choosing technology before understanding users, scale, and constraints. It also provides a way to compare trade-offs involving performance, reliability, cost, and operational complexity.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it for system-design interviews, capacity planning, service architecture, and designs involving scaling, high availability, rate limiting, caching, databases, or message queues.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/xiaohei-info/oh-my-multica/software-design-system-design
Install

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.

Any agent
npx skills add xiaohei-info/oh-my-multica --skill software-design-system-design
Clone the repo
git clone --depth 1 https://github.com/xiaohei-info/oh-my-multica

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for software-design-system-design

README.md
[![agentmods](https://agentmods.dev/badge/skills/xiaohei-info/oh-my-multica/software-design-system-design/github.svg)](https://agentmods.dev/skills/xiaohei-info/oh-my-multica/software-design-system-design)
Your own site
<a href="https://agentmods.dev/skills/xiaohei-info/oh-my-multica/software-design-system-design"><img src="https://agentmods.dev/badge/skills/xiaohei-info/oh-my-multica/software-design-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.

agentmods 80×15 button for software-design-system-design

Your own site · 80×15
<a href="https://agentmods.dev/skills/xiaohei-info/oh-my-multica/software-design-system-design"><img src="https://agentmods.dev/badge/skills/xiaohei-info/oh-my-multica/software-design-system-design.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 119 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,108 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00119 $0.04108
Opus 5 $0.00060 $0.02054
Sonnet 5 $0.00024 $0.00822
Haiku 4.5 $0.00012 $0.00411

Measured 11d ago against content hash 0eaa715b50f3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

software-design-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 11d 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.

src/omac/agents/architect/skills/software-design-system-design/SKILL.md · 225 lines

How it starts

The opening of the file, as written. The whole thing — 225 lines — stays where its author put it; the contents beside it link to each section on GitHub.

System Design Framework

A structured approach to designing large-scale distributed systems. Apply these principles when architecting new services, reviewing system designs, estimating capacity, or preparing for system design discussions.

Core Principle

Start with requirements, not solutions. Every system design begins by clarifying what you are building, for whom, and at what scale. Jumping to architecture before understanding constraints produces over-engineered or under-engineered systems.

The foundation: Scalable systems are not invented from scratch -- they are assembled from well-understood building blocks (load balancers, caches, queues, databases, CDNs) connected by clear data flows. The skill lies in choosing the right blocks, sizing them correctly, and understanding the tradeoffs each choice introduces. A four-step process -- scope, high-level design, deep dive, wrap-up -- keeps the design focused and communicable.

Scoring

Goal: 10/10. When reviewing or creating system designs, rate them 0-10 based on adherence to the principles below. A 10/10 means the design clearly states requirements, includes back-of-the-envelope estimates, uses appropriate building blocks, addresses scaling and reliability, and acknowledges tradeoffs. Lower scores indicate gaps to address. Always provide the current score and specific improvements needed to reach 10/10.

The System Design Framework

Six areas for building reliable, scalable distributed systems:

1. The Four-Step Process

Core concept: Every system design follows four stages: (1) understand the problem and establish design scope, (2) propose a high-level design and get buy-in, (3) dive deep into critical components, (4) wrap up with tradeoffs and future improvements.

Why it works: Without a structured process, designs either stay too abstract or get lost in premature detail. The four-step approach ensures you invest time proportionally -- broad strokes first, depth where it matters.

Read the full file on GitHub · 225 lines

Files

What ships with it

6 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.

Changes

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.

  1. 11d ago First seen · 225 lines · 119 tokens per session scan A 0eaa715b50f3

Subscribe to this mod's changes

software-design-system-design is a skill published in the GitHub repository xiaohei-info/oh-my-multica (26 stars, last pushed 4d ago), licensed MIT. It adds 119 tokens to every session and 4,108 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 2026-08-30.