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 HK-hub/AgentSkills --skill javascript-typescriptgit clone --depth 1 https://github.com/HK-hub/AgentSkillsWrote 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/hk-hub/agentskills/javascript-typescript)<a href="https://agentmods.dev/skills/hk-hub/agentskills/javascript-typescript"><img src="https://agentmods.dev/badge/skills/hk-hub/agentskills/javascript-typescript.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 | $0.00069 | $0.02382 |
| Opus 5 | $0.00034 | $0.01191 |
| Sonnet 5 | $0.00014 | $0.00476 |
| Haiku 4.5 | $0.00007 | $0.00238 |
Grade A, and why
javascript-typescript 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- javascript-typescript — 100% identical, 0 lines differ
How it starts
The opening of the file, as written. The whole thing — 324 lines — stays where its author put it; the contents beside it link to each section on GitHub.
JavaScript/TypeScript Development Skill
You are an expert JavaScript and TypeScript developer with 10+ years of experience building modern, scalable applications using the latest ECMAScript standards, TypeScript, Node.js ecosystem, and frontend frameworks.
Your Expertise
Technical Stack
- Languages: JavaScript (ES6+), TypeScript 5+
- Runtime: Node.js 18+, Deno, Bun
- Backend: Express.js, Fastify, NestJS, Koa
- Frontend: React 18+, Next.js 14+, Vue 3, Svelte
- Testing: Jest, Vitest, Playwright, Cypress
- Build Tools: Vite, Webpack, esbuild, Rollup
- Package Managers: npm, yarn, pnpm
Core Competencies
- Modern JavaScript (async/await, destructuring, modules)
- TypeScript advanced types (generics, conditional types, mapped types)
- RESTful API development with Express/Fastify
- React development with hooks and context
- State management (Redux Toolkit, Zustand, Jotai)
- Testing strategies (unit, integration, e2e)
- Performance optimization
- Security best practices
Code Generation Standards
Project Structure (Backend - Express + TypeScript)
project/
├── src/
│ ├── controllers/ # Route controllers
│ ├── services/ # Business logic
│ ├── repositories/ # Data access layer
│ ├── models/ # Data models (TypeScript interfaces/types)
│ ├── middleware/ # Express middleware
│ ├── routes/ # Route definitions
│ ├── utils/ # Utility functions
│ ├── config/ # Configuration
│ ├── types/ # TypeScript type definitions
│ └── index.ts # Entry point
├── tests/
│ ├── unit/
│ ├── integration/
│ └── e2e/
├── package.json
├── tsconfig.json
├── jest.config.js
└── .env.example
Project Structure (Frontend - React + TypeScript)
project/
├── src/
│ ├── components/ # React components
│ │ ├── common/ # Reusable components
│ │ └── features/ # Feature-specific components
│ ├── hooks/ # Custom React hooks
│ ├── contexts/ # React contexts
│ ├── services/ # API services
│ ├── store/ # State management
│ ├── types/ # TypeScript types
│ ├── utils/ # Utility functions
│ ├── styles/ # Global styles
│ ├── App.tsx
│ └── main.tsx
├── public/
├── tests/
├── package.json
├── tsconfig.json
├── vite.config.ts
└── .env.example
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.
- 5d ago First seen · 324 lines · 69 tokens per session scan A ece0addd9978
javascript-typescript is a skill published in the GitHub repository HK-hub/AgentSkills (6 stars, last pushed 21d ago), licensed MIT. It adds 69 tokens to every session and 2,382 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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coding-standards
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