Borrowing it
Nothing to install: this file belongs to YankielDBC2/codex-skills-library. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/YankielDBC2/codex-skills-library/main/.agents/skills/backend-clean-architecture/SKILL.mdgit clone --depth 1 https://github.com/YankielDBC2/codex-skills-libraryWrote 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/yankieldbc2/codex-skills-library/backend-clean-architecture)<a href="https://agentmods.dev/skills/yankieldbc2/codex-skills-library/backend-clean-architecture"><img src="https://agentmods.dev/badge/skills/yankieldbc2/codex-skills-library/backend-clean-architecture/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/yankieldbc2/codex-skills-library/backend-clean-architecture"><img src="https://agentmods.dev/badge/skills/yankieldbc2/codex-skills-library/backend-clean-architecture.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 | $0.00029 | $0.00435 |
| Opus 5 | $0.00015 | $0.00217 |
| Sonnet 5 | $0.00006 | $0.00087 |
| Haiku 4.5 | $0.00003 | $0.00044 |
Grade A, and why
backend-clean-architecture 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 8d 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
Backend Clean Architecture
Goal
Produce backend code that is small, testable, reusable, and easy to reason about. Keep orchestration at the edges and business behavior in focused modules.
When to use
Use for backend features, API routes, controllers, services, database logic, auth, validation, error handling, and backend refactors.
When not to use
Do not use for frontend-only UI work, copywriting, visual design, or unrelated project management tasks.
Read first
- The affected route/controller/handler.
- Direct service/use-case imports.
- Existing validator/schema/error helpers.
- Database model/repository only if persistence changes.
- Related tests if behavior changes.
Do not scan the whole backend unless the task requires an architecture review.
Workflow
- Identify the real owner of the behavior.
- Keep request parsing and response formatting in routes/controllers.
- Put business logic in services or use-cases.
- Put persistence in repositories or query modules.
- Reuse validation, auth, mapping, and error helpers.
- Preserve public behavior unless the user asked for a behavior change.
- Add regression coverage at the smallest meaningful seam.
- Delete obsolete paths when safe.
Architecture rules
- Routes/controllers parse request, call service/use-case, return response.
- Services/use-cases own business logic.
- Repositories/query modules own data access.
- Validators/schemas own input validation.
- Error helpers own normalized error responses.
- Auth/session helpers own identity and permission checks.
- External API calls live behind clients/adapters.
- Do not introduce hidden global state.
Validation
Run available relevant commands: typecheck, lint, unit tests for affected modules, integration tests for changed endpoints, and build when meaningful.
Final response
Report changed files, architecture decisions, validation output, and any known risks.
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.
- 8d ago First seen · 62 lines · 29 tokens per session scan A 765ae923b83b
backend-clean-architecture is a skill published in the GitHub repository YankielDBC2/codex-skills-library (10 stars, last pushed 1mo ago), licensed MIT. It adds 29 tokens to every session and 435 once invoked, about $0.0001 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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