writing-typescript

writing-typescript is a skill for Claude Code, Codex from alexei-led/cc-thingz. It costs 78 tokens per session (858 once invoked), scanned A, original, MIT.

Guidance for writing TypeScript, a version of JavaScript that adds type checking, including TypeScript used with Node.js and React.

In plain words
What is it for?
Use it when creating or changing TypeScript files, React components, Node.js services, typed APIs, data models, validation, or TypeScript tests.
Why use it?
It helps keep data, API boundaries, asynchronous code, and tests predictable while following the project's existing tools and settings.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it when creating or changing TypeScript files, React components, Node.js services, typed APIs, data models, validation, or TypeScript tests.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/alexei-led/cc-thingz/writing-typescript
Install

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.

Any agent
npx skills add alexei-led/cc-thingz --skill writing-typescript
Clone the repo
git clone --depth 1 https://github.com/alexei-led/cc-thingz

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for writing-typescript

README.md
[![agentmods](https://agentmods.dev/badge/skills/alexei-led/cc-thingz/writing-typescript.svg)](https://agentmods.dev/skills/alexei-led/cc-thingz/writing-typescript)
Your own site
<a href="https://agentmods.dev/skills/alexei-led/cc-thingz/writing-typescript"><img src="https://agentmods.dev/badge/skills/alexei-led/cc-thingz/writing-typescript.svg" alt="Measured on agentmods" height="20"></a>
Per session 78 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 858 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00078 $0.00858
Opus 5 $0.00039 $0.00429
Sonnet 5 $0.00016 $0.00172
Haiku 4.5 $0.00008 $0.00086

Measured 8d ago against content hash ae0b77933c65, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

writing-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 8d 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.

src/skills/writing-typescript/SKILL.md · 68 lines

How it starts

The opening of the file, as written. The whole thing — 68 lines — stays where its author put it; the contents beside it link to each section on GitHub.

TypeScript Development

Scope

  • Use for .ts and .tsx, Node.js services, React apps, typed APIs, and TypeScript design advice.
  • Do not use for Go, Python, Rust, plain HTML/CSS/JS, or server-rendered templates.
  • Follow the repository's TypeScript version, tsconfig, package manager, framework, test runner, and lint rules.
  • Do not add dependencies or switch frameworks unless the project already uses them or the user approves.

Reference Reads

  • Read only the references needed for the task.
  • Read references/principles.md for non-trivial TypeScript changes or reviews.
  • Read references/patterns.md for data models, validation, async flow, or module boundaries.
  • Read references/react.md for .tsx, hooks, component state, forms, performance, or React tests.
  • Read references/testing.md before adding or changing TypeScript tests.
  • Read references/linting.md before changing lint config, lint commands, or slow lint workflows.

Defaults

  • Preserve strict typing; do not weaken compiler options to pass checks.
  • Use unknown for untrusted input. Avoid any; isolate it only for unavoidable interop.
  • Validate API, JSON, env, storage, and form data at the boundary before typed use.
  • Use discriminated unions for variants, async state, and domain states.
  • Use guard clauses and focused helpers. Avoid deep nesting, global state, and mixed concerns.
  • Use the project's error conventions; prefer unions or Result for recoverable failures.
  • Pass dependencies explicitly; avoid inheritance, singletons, and hidden module state.
  • Avoid unsafe casts, non-null assertions, broad index signatures, boolean-flag state, and new app enums where literal unions fit.

Comments and JSDoc

  • Use JSDoc or TSDoc for exported APIs and non-obvious public properties or methods.
  • Avoid merely restating property, parameter, or type names.
  • Add implementation comments only for non-obvious constraints, invariants, side effects, tradeoffs, or interoperability quirks.
  • Keep comments short. Move longer rationale to docs, issue links, or design notes.
  • Do not comment obvious code.
  • Keep tests readable without comments; add one only for unobvious fixtures, timers, concurrency, browser setup, or regression context.

Read the full file on GitHub · 68 lines

Files

What ships with it

6 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.

Changes

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.

  1. 8d ago First seen · 68 lines · 78 tokens per session scan A ae0b77933c65

Subscribe to this mod's changes

writing-typescript is a skill published in the GitHub repository alexei-led/cc-thingz (35 stars, last pushed 1mo ago), licensed MIT. It adds 78 tokens to every session and 858 once invoked, about $0.0004 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 2026-08-30.

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