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/quentinhsu/skills/modernizenpx skills add QuentinHsu/skills --skill modernizegit clone --depth 1 https://github.com/QuentinHsu/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/quentinhsu/skills/modernize)<a href="https://agentmods.dev/skills/quentinhsu/skills/modernize"><img src="https://agentmods.dev/badge/skills/quentinhsu/skills/modernize.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 | $0.00153 | $0.00844 |
| Opus 5 | $0.00077 | $0.00422 |
| Sonnet 5 | $0.00031 | $0.00169 |
| Haiku 4.5 | $0.00015 | $0.00084 |
Grade A, and why
refactor-modernize 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 — 59 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Refactor Modernize
Replace legacy patterns and outdated idioms with current language features and conventions — applicable to any language or project.
Detailed rules live in:
Core Principle
Modernization replaces how code expresses its intent, not what it does. The observable behavior stays the same; the implementation moves to current best practice.
When To Use
Use this skill when the task involves:
- replacing callbacks, event emitters, or manual promise chains with async/await
- replacing verbose loops with modern iteration (for-of, iterators, comprehensions, streams)
- adopting destructuring, pattern matching, optional chaining, or nullish coalescing
- converting var to let/const, or equivalent scope-tightening in other languages
- replacing class-heavy OOP with simpler functional or data-oriented patterns when the language supports it
- adopting new standard library APIs that replace third-party utilities (e.g.,
structuredClone,Object.groupBy,Array.at) - applying new edition or version features (Rust editions, Python 3.10+ match, Go generics, C# records)
- replacing hand-rolled utilities with language built-ins
Working Mode
- Identify baseline. Determine the project's target language version / runtime version from config files (tsconfig, pyproject, go.mod, Cargo.toml, etc.).
- Scan for legacy patterns. Look for patterns that have a modern equivalent in the target version.
- Apply language feature rules. Replace syntax-level legacy patterns. See rules/language-features.md.
- Apply async and concurrency rules. Modernize asynchronous code and concurrency primitives. See rules/async-concurrency.md.
- Apply idiom rules. Replace outdated conventions with current idiomatic patterns. See rules/idioms.md.
- Verify. Run tests. Modern syntax should produce identical behavior — any test failure signals a semantic mismatch, not just a style issue.
What ships with it
3 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.
- 4d ago First seen · 59 lines · 153 tokens per session scan A 515d7b377639
refactor-modernize is a skill published in the GitHub repository QuentinHsu/skills (2 stars, last pushed 1mo ago), licensed MIT. It adds 153 tokens to every session and 844 once invoked, about $0.0008 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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