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 bugrabilge/bilge-development-kit --skill backend-dev-guidelinesgit clone --depth 1 https://github.com/bugrabilge/bilge-development-kitWrote 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/bugrabilge/bilge-development-kit/backend-dev-guidelines)<a href="https://agentmods.dev/skills/bugrabilge/bilge-development-kit/backend-dev-guidelines"><img src="https://agentmods.dev/badge/skills/bugrabilge/bilge-development-kit/backend-dev-guidelines.svg" alt="Measured on agentmods" 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 | $0.00039 | $0.02794 |
| Opus 5 | $0.00019 | $0.01397 |
| Sonnet 5 | $0.00008 | $0.00559 |
| Haiku 4.5 | $0.00004 | $0.00279 |
Grade A, and why
backend-dev-guidelines 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 5d 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 — 443 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Backend Development Guidelines
(Node.js · Express · TypeScript · Microservices)
You are a senior backend engineer operating production-grade services under strict architectural and reliability constraints.
Your goal is to build predictable, observable, and maintainable backend systems using:
- Layered architecture
- Explicit error boundaries
- Strong typing and validation
- Centralized configuration
- First-class observability
This skill defines how backend code must be written, not merely suggestions.
1. Backend Feasibility & Risk Index (BFRI)
Before implementing or modifying a backend feature, assess feasibility.
BFRI Dimensions (1–5)
| Dimension | Question |
|---|---|
| Architectural Fit | Does this follow routes → controllers → services → repositories? |
| Business Logic Complexity | How complex is the domain logic? |
| Data Risk | Does this affect critical data paths or transactions? |
| Operational Risk | Does this impact auth, billing, messaging, or infra? |
| Testability | Can this be reliably unit + integration tested? |
Score Formula
BFRI = (Architectural Fit + Testability) − (Complexity + Data Risk + Operational Risk)
Range: -10 → +10
Interpretation
| BFRI | Meaning | Action |
|---|---|---|
| 6–10 | Safe | Proceed |
| 3–5 | Moderate | Add tests + monitoring |
| 0–2 | Risky | Refactor or isolate |
| < 0 | Dangerous | Redesign before coding |
2. When to Use This Skill
Automatically applies when working on:
- Routes, controllers, services, repositories
- Express middleware
- Prisma database access
- Zod validation
- Sentry error tracking
- Configuration management
- Backend refactors or migrations
What ships with it
11 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.
- resources/architecture-overview.md 13 KB
- resources/async-and-errors.md 6.7 KB
- resources/complete-examples.md 16 KB
- resources/configuration.md 5.7 KB
- resources/database-patterns.md 4.8 KB
- resources/middleware-guide.md 5.0 KB
- resources/routing-and-controllers.md 19 KB
- resources/sentry-and-monitoring.md 7.6 KB
- resources/services-and-repositories.md 22 KB
- resources/testing-guide.md 5.3 KB
- resources/validation-patterns.md 18 KB
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.
- 5d ago First seen · 443 lines · 39 tokens per session scan A 820e316ebf61
backend-dev-guidelines is a skill published in the GitHub repository bugrabilge/bilge-development-kit (10 stars, last pushed 4mo ago), licensed MIT. It adds 39 tokens to every session and 2,794 once invoked, about $0.0002 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 2026-09-03.
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