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 magnus919/agent-skills --skill programming-principlesgit clone --depth 1 https://github.com/magnus919/agent-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/magnus919/agent-skills/programming-principles)<a href="https://agentmods.dev/skills/magnus919/agent-skills/programming-principles"><img src="https://agentmods.dev/badge/skills/magnus919/agent-skills/programming-principles.svg" alt="Measured on agentmods" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00053 | $0.04035 |
| Opus 5 | $0.00026 | $0.02018 |
| Sonnet 5 | $0.00011 | $0.00807 |
| Haiku 4.5 | $0.00005 | $0.00404 |
Grade A, and why
programming-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 4d 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 — 347 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Programming Principles (14 Books)
Principles distilled from the mattpocock/agent-rules-books repo — 14 pre-made
AGENTS.md rule sets derived from classic software engineering books. Use this
skill directly during code review, refactoring, design, and implementation.
For deeper per-book coverage, load the relevant reference file.
Task-to-Book Mapping
When the task involves... Load / apply principles from ──────────────────────────────────────────────────────────────────────── Everyday implementation & code review Clean Code, Code Complete Refactoring existing code Refactoring, WELC Architecture / dependency management Clean Architecture, APoSD Domain modeling / business rules DDD, DDD Distilled, IDDD Enterprise app patterns / layering PoEAA Production reliability / stability Release It! Data consistency / scalability / events DDIA Engineering craft / automation Pragmatic Programmer Designing APIs / module boundaries APoSD Legacy code / risky changes WELC, Refactoring
How to Perform a Code Assessment
For a structured, reproducible workflow that combines book principles with
actual repo exploration, see references/code-assessment-workflow.md. It
covers: loading the evaluation framework, reading the repo and GitHub context,
deduplicating against existing issues/PRs, classifying findings by book +
priority, and deciding whether each merits an issue.
Cross-Cutting Principles
Principles synthesized from multiple books, organized by concern.
Naming & Communication
- One term per concept across the codebase. RENAMING is design work.
- Names reveal abstraction, not mechanism. Prefer domain vocabulary over technical implementation detail.
- Functions are verbs, classes/types are nouns, booleans are predicates.
- A name needing a comment to explain it is the wrong name.
- Comments exist for rationale, contracts, warnings, and non-obvious constraints — never to narrate code or compensate for bad names.
What ships with it
33 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.
- evals/evals.json 13 KB
- README.md 2.1 KB
- references/a-philosophy-of-software-design.full.md 13 KB
- references/a-philosophy-of-software-design.mini.md 5.6 KB
- references/clean-architecture.full.md 17 KB
- references/clean-architecture.mini.md 5.4 KB
- references/clean-code.full.md 14 KB
- references/clean-code.mini.md 3.7 KB
- references/code-assessment-workflow.md 4.4 KB
- references/code-complete.full.md 12 KB
- references/code-complete.mini.md 6.6 KB
- references/designing-data-intensive-apps.full.md 16 KB
- references/designing-data-intensive-apps.mini.md 6.8 KB
- references/domain-driven-design-distilled.full.md 11 KB
- references/domain-driven-design-distilled.mini.md 2.5 KB
- references/domain-driven-design.full.md 41 KB
- references/domain-driven-design.mini.md 3.5 KB
- references/implementing-domain-driven-design.full.md 13 KB
- references/implementing-domain-driven-design.mini.md 4.9 KB
- references/patterns-of-eaa.full.md 15 KB
- references/patterns-of-eaa.mini.md 2.6 KB
- references/refactoring-guru.full-smells-and-priorities.md 31 KB
- references/refactoring-guru.full-technique-playbook-and-safety.md 30 KB
- references/refactoring-guru.full.md 1.1 KB
- references/refactoring-guru.mini.md 2.3 KB
- references/refactoring.full.md 17 KB
- references/refactoring.mini.md 2.5 KB
- references/release-it.full.md 13 KB
- references/release-it.mini.md 2.4 KB
- references/the-pragmatic-programmer.full.md 13 KB
- references/the-pragmatic-programmer.mini.md 2.8 KB
- references/working-effectively-with-legacy-code.full.md 13 KB
- references/working-effectively-with-legacy-code.mini.md 2.3 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.
- 4d ago First seen · 347 lines · 53 tokens per session scan A 0a5f9d1365f1
programming-principles is a skill published in the GitHub repository magnus919/agent-skills (70 stars, last pushed yesterday), licensed MIT. It adds 53 tokens to every session and 4,035 once invoked, about $0.0003 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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review
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lean-review
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stage-coach
Consume CocoSentinel per-stage external coach requests and produce stage quality scores.
review-export
Export CocoReview reports as markdown, html, or pdf-ready status artifacts. Usage: $review export markdown|html|pdf [report-path].
community-research-insight
Extract structured insight briefs from community research transcripts or notes. Produces pain points, stakeholder needs, opportunity maps, risks, and follow-up questions. Requires human review before publication.