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 agentmods add skills/elct9620/ai-coding-skills/principlesnpx skills add elct9620/ai-coding-skills --skill principlesgit clone --depth 1 https://github.com/elct9620/ai-coding-skillsWrote 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/elct9620/ai-coding-skills/principles)<a href="https://agentmods.dev/skills/elct9620/ai-coding-skills/principles"><img src="https://agentmods.dev/badge/skills/elct9620/ai-coding-skills/principles.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 | $0.00094 | $0.00793 |
| Opus 5 | $0.00047 | $0.00396 |
| Sonnet 5 | $0.00019 | $0.00159 |
| Haiku 4.5 | $0.00009 | $0.00079 |
Grade A, and why
principles 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 6d 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 — 78 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Related Skills
- Detected a code smell (long method, feature envy)? → Use refactoring for specific techniques
- Need a specific pattern (Strategy, Factory)? → Use design-patterns for selection and implementation
- Deciding which architectural layer or structure code belongs in? → Use architecture
Applicability Rubric
| Condition | Pass | Fail |
|---|---|---|
| New feature from scratch | Building without existing reference | Modifying existing code |
| Design trade-off | Choosing between competing approaches | Implementation path is clear |
| Interface/boundary design | Defining class responsibilities or contracts | Internal implementation detail |
| Dependency structure | Deciding coupling and injection strategy | No dependency decisions |
Apply when: Any condition passes Do NOT apply when: The task is purely about restructuring existing code (use refactoring) or detecting code smells (use refactoring)
Core Principles
SOLID
| Principle | Description | Violation Sign |
|---|---|---|
| Single Responsibility | One reason to change | Class does too many things |
| Open/Closed | Open for extension, closed for modification | Frequent changes to existing code |
| Liskov Substitution | Subtypes must be substitutable | Type checks or conditional logic on types |
| Interface Segregation | Many specific interfaces over one general | Clients implement unused methods |
| Dependency Inversion | Depend on abstractions, not concretions | Direct instantiation of dependencies |
KISS (Keep It Simple, Stupid)
- Prefer straightforward solutions
- Avoid unnecessary complexity
- Write code that's easy to understand
- If it's hard to explain, it's too complex
DRY (Don't Repeat Yourself)
- Extract repeated logic into functions
- BUT: Premature abstraction is worse than duplication
- Rule of three: Abstract after third repetition
- Accept some duplication for clarity
YAGNI (You Aren't Gonna Need It)
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.
- 6d ago First seen · 78 lines · 94 tokens per session scan A e64bbc6603c1
principles is a skill published in the GitHub repository elct9620/ai-coding-skills (5 stars, last pushed 10d ago), licensed Apache-2.0. It adds 94 tokens to every session and 793 once invoked, about $0.0005 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.
Other skills, from other repositories
systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.
local-ai-agents
Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…
chronicle
Analyze Copilot session history for standup reports, usage tips, session search, and session reindexing. Use when the user asks for a standup, daily summary, usage tips, workflow recommendations, wants to search or find past sessions by keyword/file/PR, wants to reindex their session store, or asks about deleting…
chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…
next-cache-components-adoption
Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…