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.
git clone --depth 1 https://github.com/Ashfaqbs/software-dev-ai-claude-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/commands/ashfaqbs/software-dev-ai-claude-toolkit/system-design)<a href="https://agentmods.dev/commands/ashfaqbs/software-dev-ai-claude-toolkit/system-design"><img src="https://agentmods.dev/badge/commands/ashfaqbs/software-dev-ai-claude-toolkit/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/commands/ashfaqbs/software-dev-ai-claude-toolkit/system-design"><img src="https://agentmods.dev/badge/commands/ashfaqbs/software-dev-ai-claude-toolkit/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 | $0.00006 | $0.00377 |
| Opus 5.5 | $0.00002 | $0.00151 |
| Sonnet 5.5 | $0.00001 | $0.00075 |
| Haiku 4.5 | $0.00001 | $0.00038 |
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 1mo 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.
What it actually says
System Design
Help me think through the system design for: $ARGUMENTS
Framework
Walk through these areas step by step. Ask me clarifying questions at each step before moving on.
1. Requirements
- What are the functional requirements?
- What are the non-functional requirements (latency, throughput, availability, consistency)?
- What scale are we designing for? (users, requests/sec, data volume)
2. High-Level Architecture
- What are the main components/services?
- How do they communicate (sync REST/gRPC vs async Kafka/queues)?
- Draw the architecture using text diagrams.
3. Data Design
- What data needs to be stored?
- SQL vs NoSQL decisions for each entity (and why).
- Schema design, indexing strategy, partitioning/sharding if needed.
4. API Design
- Key endpoints between services and to clients.
- Authentication and authorization approach.
5. Scaling & Performance
- Where are the bottlenecks?
- Caching strategy (what, where, TTL, invalidation).
- Database read replicas, connection pooling, query optimization.
- Horizontal scaling approach.
6. Reliability
- Single points of failure and how to eliminate them.
- Failure modes and graceful degradation.
- Monitoring, alerting, circuit breakers.
Rules
- Explain trade-offs for every decision (e.g., "CP vs AP", "SQL vs NoSQL for this use case").
- Use real numbers when estimating (requests/sec, storage in GB, latency in ms).
- Reference technologies I know: Spring Boot, FastAPI, PostgreSQL, MongoDB, Redis, Kafka, Flink, Docker, K8s.
- This is a learning exercise — teach me the reasoning, not just the answer.
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.
- 1mo ago First seen · 48 lines · 6 tokens per session scan A 5dcf37454d0e
system-design is a command published in the GitHub repository Ashfaqbs/software-dev-ai-claude-toolkit (27 stars, last pushed 1mo ago), licensed MIT. It adds 6 tokens to every session and 377 once invoked, about $0.0000 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.
Other commands, from other repositories
cors
Scan an endpoint for CORS misconfiguration — arbitrary-origin reflection, null-origin trust, credential exposure, suffix/prefix regex bypass, scheme downgrade. Usage: /cors [--cookie "session=..."] | /cors -l urls.txt.
contract
Contract-First — defines the interface, writes contract tests, then implements. Use when building a new component or port and the abstraction must come before the code.
dev-api
Create or document REST, GraphQL, or tRPC endpoints, with a versioning strategy.
dev-error-handling
Implements a robust and consistent error handling strategy.
new-agents-md
Generate a vendor-neutral AGENTS.md by projecting this Claude-Code instruction corpus — CLAUDE.md tree, architectural rules, warning/feedback landmines, canonical commands — into a flat file other coding agents (Codex, Cursor, Aider, …) can read, then interviewing only for the gaps the corpus can't know.
coordinate
Keep multiple live Claude sessions aligned via a shared, gitignored session board (.claude/sessions-active.md) — register what this session owns, see what others own, leave hand-off notes, detect file/slug collisions. A session can claim coordinator to assign work to others. No daemon/polling.