JavaScript Language Patterns SKILL.md skillA
JavaScript Language Patterns from hoangnguyen0403/agent-skills-standard is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add hoangnguyen0403/agent-skills-standard/JavaScript Language Patterns@git:20260509.3e36716Pins git:20260509.3e36716 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- hoangnguyen0403/agent-skills-standard
- Path
.agents/skills/javascript/language/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260509.3e36716, committed May 9, 2026
- Size
- 1,718 bytes
- Repository stars
- 583
- License
- MIT
Modern JavaScript (ES2022+) patterns for clean, maintainable code.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# JavaScript Language Patterns
## **Priority: P0 (CRITICAL)**
Modern JavaScript standards for clean, maintainable code.
## Implementation Guidelines
- **Variables**: `const` default. `let` if needed. No `var`.
- **Functions**: Arrows for callbacks. Declarations for top-level.
- **Async**: `async/await` + `try/catch`.
- **Objects**: Destructuring, Spread `...`, Optional Chain `?.`, Nullish `??`.
- **Strings**: Template literals `${}`.
- **Arrays**: `map`, `filter`, `reduce`. No loops.
- **Modules**: ESM `import`/`export`. Export only what is necessary.
- **Classes**: Use `#private` fields for true privacy.
## Anti-Patterns
- **No `var`**: Block scope only.
- **No `==`**: Strict `===`.
- **No `new Object()`**: Use literals `{}`.
- **No Callbacks**: Promisify everything.
- **No Mutation**: Immutability first.
## Code
```javascript
// Modern Syntax
const [x, ...rest] = items;
const name = user?.profile?.name ?? 'Guest';
// Async
async function getUser(id) {
try {
const res = await fetch(`/api/${id}`);
return res.json();
} catch (err) {
console.error(err);
throw err;
}
}
// Class + Private
class Service {
#key;
constructor(k) {
this.#key = k;
}
…Read the whole file at its exact version.
How to install
mdr add hoangnguyen0403/agent-skills-standard/JavaScript Language Patterns@sha256:9d13120ef003a124The line at the top of this page pins the label git:20260509.3e36716, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_qpi7l7vsdhv6v5za)
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Versions
The registry has recorded 1 version of this file, committed on May 9, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (1718 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
hoangnguyen0403/agent-skills-standard · 583 stars · license MIT · pushed 2026-11-07 · branch develop
API
GET https://markdownregistry.com/api/v1/artifacts/art_qpi7l7vsdhv6v5za GET https://markdownregistry.com/api/v1/resolve?ref=hoangnguyen0403/agent-skills-standard/JavaScript Language Patterns GET https://markdownregistry.com/api/v1/blob/9d13120ef003a12437d9be9bdebeeb9515844b37176a2dabf36ec4096d9509e6
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.