🎯

ts-check-jsdoc-experiment

🎯Skill

from marius-townhouse/effective-typescript-skills

What it does

Enables gradual TypeScript type checking in JavaScript files using @ts-check and JSDoc annotations without full conversion.

📦

Part of

marius-townhouse/effective-typescript-skills(83 items)

ts-check-jsdoc-experiment

Installation

Quick InstallInstall with npx

npx skills add marius-townhouse/effective-typescript-skills --all

Quick InstallInstall with npx

npx skills add marius-townhouse/effective-typescript-skills -s prefer-unknown-over-any exhaustiveness-checking

Quick InstallInstall with npx

npx skills add marius-townhouse/effective-typescript-skills -a opencode claude-code

Quick InstallInstall with npx

npx skills add marius-townhouse/effective-typescript-skills -l

git cloneClone repository

git clone https://github.com/marius-townhouse/effective-typescript-skills.git

📖 Extracted from docs: marius-townhouse/effective-typescript-skills

Need more details? View full documentation on GitHub →

1Installs

AddedFeb 4, 2026

View on GitHub Back to Skills

Skill Details

SKILL.md

Use when experimenting with TypeScript. Use when migrating JavaScript gradually. Use when adding types to JS files. Use when teams are learning TypeScript. Use when validating JavaScript with types.

Overview

# Use @ts-check and JSDoc to Experiment with TypeScript

Overview

You can add TypeScript type checking to JavaScript files without converting them to TypeScript. Use @ts-check at the top of a JS file and JSDoc annotations to add types. This lets you experiment with TypeScript gradually without committing to the full conversion.

When to Use This Skill

Experimenting with TypeScript
Gradually migrating JavaScript
Adding types to JS files
Teams learning TypeScript
Validating JavaScript with types

The Iron Rule

Use @ts-check and JSDoc to add TypeScript checking to JavaScript files without full conversion.

Example

```javascript

// @ts-check

/**

* @param {string} name

* @param {number} age

* @returns {string}

function greet(name, age) {

return Hello ${name}, you are ${age};

}

greet('Alice', 30); // OK

greet('Alice', '30'); // Type error!

/* @type {string[]} /

const names = ['Alice', 'Bob'];

/* @typedef {{ x: number, y: number }} Point /

/* @type {Point} /

const point = { x: 1, y: 2 };

```

Reference

Effective TypeScript, 2nd Edition by Dan Vanderkam
Item 80: Use @ts-check and JSDoc to Experiment with TypeScript

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