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 DauQuangThanh/hanoi-rainbow --skill backend-designgit clone --depth 1 https://github.com/DauQuangThanh/hanoi-rainbowWrote 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/dauquangthanh/hanoi-rainbow/backend-design)<a href="https://agentmods.dev/skills/dauquangthanh/hanoi-rainbow/backend-design"><img src="https://agentmods.dev/badge/skills/dauquangthanh/hanoi-rainbow/backend-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/dauquangthanh/hanoi-rainbow/backend-design"><img src="https://agentmods.dev/badge/skills/dauquangthanh/hanoi-rainbow/backend-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 | $0.00086 | $0.00901 |
| Opus 5 | $0.00043 | $0.00451 |
| Sonnet 5 | $0.00017 | $0.00180 |
| Haiku 4.5 | $0.00009 | $0.00090 |
Grade A, and why
backend-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 10d 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 — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Backend Design
Workflow
Follow this systematic design process:
-
Requirements Analysis
- Gather functional requirements (features, operations)
- Define non-functional requirements (performance, scalability, availability)
- Identify constraints (budget, timeline, technology, compliance)
-
Architecture Selection
- Choose architecture pattern (monolith, microservices, serverless)
- Select technology stack based on requirements
- Define service boundaries and responsibilities
-
API Design
- Design RESTful endpoints with proper resource modeling
- Define request/response schemas and contracts
- Plan versioning strategy and documentation
- See api-design-guide.md for REST/GraphQL/gRPC patterns
-
Database Design
- Model entities and relationships
- Design schema with normalization
- Plan indexing and partitioning strategies
- See database-design.md for relational and NoSQL patterns
-
Security Design
- Design authentication flow (OAuth 2.0, JWT)
- Plan authorization model (RBAC, ABAC)
- Define data encryption and protection strategy
-
Scalability & Performance
- Design caching strategy (Redis, CDN)
- Plan load balancing and auto-scaling
- Define asynchronous processing with message queues
-
Documentation
- Create API specifications (OpenAPI/Swagger)
- Document architecture decisions with Mermaid diagrams
- Provide implementation guidelines and roadmap
Output Structure
Present your backend design with these sections:
- System Overview - High-level architecture, components, technology stack
- API Specification - Endpoints, schemas, authentication, OpenAPI docs
- Database Design - ERD, schema, indexes, migration plan
- Architecture Decisions - Service decomposition, communication patterns, consistency model
- Security Implementation - Authentication/authorization flows, encryption
- Scalability Plan - Load balancing, caching, database scaling, auto-scaling
- Deployment Architecture - Containers, infrastructure, CI/CD, monitoring
- Implementation Roadmap - Phases, milestones, dependencies, risks
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.
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.
- 10d ago First seen · 85 lines · 86 tokens per session scan A d6444253116c
backend-design is a skill published in the GitHub repository DauQuangThanh/hanoi-rainbow (16 stars, last pushed 7mo ago), licensed MIT. It adds 86 tokens to every session and 901 once invoked, about $0.0004 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.
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