JavaScript Development Standards

Core JavaScript development standards covering modern JavaScript features (ES2022+), code quality practices, async programming patterns, and JSDoc documentation.

Enforcement

• Prohibited actions: Do not invent script arguments not documented below; do not skip analysis before fixing
• Constraints: All script calls use Rule 9 explicit notation (python3 .plan/execute-script.py pm-dev-frontend:javascript:jsdoc {subcommand} {args})

Prerequisites

• ES2015+ and ES modules
• npm and JavaScript build tools

Workflow

Step 1: Load Core Patterns

Load this standard for any JavaScript implementation work.

Read: standards/javascript-fundamentals.md

Covers ES modules, variables, functions, and vanilla JS preference.

Step 2: Load Additional Standards (As Needed)

Code Quality (load for refactoring or reviews):

Read: standards/code-quality.md

Use when: Reviewing code complexity, applying refactoring patterns, or enforcing quality limits.

Modern Patterns (load for new code):

Read: standards/modern-patterns.md

Use when: Writing new code using destructuring, template literals, spread/rest, array methods, or class patterns.

Security (DOM trust boundaries / XSS prevention):

The JavaScript security surface — DOM trust boundaries, XSS sinks, sanitization, and Trusted Types — is owned by Skill: pm-dev-frontend:javascript-security. Load that skill for any security-sensitive review or hardening task; it resolves through the security profile and references the DOM-trust/XSS content under this skill's standards/modern-patterns.md.

Async Programming (load for async code):

Read: standards/async-programming.md

Use when: Working with Promises, async/await, error handling, or concurrency patterns.

JSDoc Essentials (load for documentation work):

Read: standards/jsdoc-essentials.md

Use when: Documenting JavaScript code, setting up JSDoc and ESLint integration, or reviewing documentation quality. Covers required tags, type annotations, writing style, and build integration.

JSDoc Patterns (load for documentation patterns):

Read: standards/jsdoc-patterns.md

Use when: Documenting functions, classes, modules, types, or web components (Lit). Provides patterns with examples for each code element type.

Workflow: Analyze JSDoc Violations

Use when: Identifying missing or incomplete JSDoc documentation across files or directories.

1. Run violation analysis script

# Analyze entire directory
python3 .plan/execute-script.py pm-dev-frontend:javascript:jsdoc analyze --directory src/

# Analyze single file
python3 .plan/execute-script.py pm-dev-frontend:javascript:jsdoc analyze --file src/utils/formatter.js

# Analyze only for missing JSDoc (skip syntax checks)
python3 .plan/execute-script.py pm-dev-frontend:javascript:jsdoc analyze --directory src/ --scope missing

# Analyze only JSDoc syntax issues
python3 .plan/execute-script.py pm-dev-frontend:javascript:jsdoc analyze --directory src/ --scope syntax

2. Process violation results

Review violations categorized by severity:

• CRITICAL: Exported/public API without JSDoc
• WARNING: Internal function without JSDoc, missing @param/@returns
• SUGGESTION: Missing optional tags (@example, @fileoverview)

Fix CRITICAL violations first (exported functions/classes), then WARNING, then SUGGESTION (optional).

Violation Types

• missing_jsdoc - Function/class entirely missing JSDoc
• missing_class_doc - Class without documentation
• missing_constructor_doc - Constructor with parameters undocumented
• missing_param - @param tag missing for parameter
• missing_param_type - Type annotation missing in @param
• missing_returns - @returns tag missing for return value
• missing_fileoverview - No @fileoverview at file level

Scope Options

• all - Check for missing JSDoc and syntax issues (default)
• missing - Only check for missing JSDoc documentation
• syntax - Only check JSDoc syntax and completeness

Canonical invocations

The canonical argparse surface for jsdoc.py. The plugin-doctor analyzer (_analyze_manage_invocation.py) reads this section as source-of-truth for the manage-invocation-invalid and missing-canonical-block rules. Consuming docs xref this section by name instead of restating the command inline. See `pm-plugin-development:plugin-script-architecture` cross-skill-integration.md § "Script invocation in documentation".

analyze

python3 .plan/execute-script.py pm-dev-frontend:javascript:jsdoc analyze \
  (--directory DIRECTORY | --file FILE) [--scope {all,missing,syntax}]

--directory and --file are mutually exclusive; exactly one must be supplied.

Related Skills

• plan-marshall:ref-code-quality - Language-agnostic code quality and documentation principles
• pm-dev-frontend:css - CSS standards
• pm-dev-frontend:lint-config - ESLint, Prettier, Stylelint configuration
• Anthropic frontend-design skill - Visual-aesthetic guidance (distinctive, production-grade UI; avoiding generic "AI slop" design). Complementary to this skill: javascript governs code standards, frontend-design governs visual aesthetics. Pointer only — no content duplicated here.