Babel Config Validator

Validate Babel config files (babel.config.json, .babelrc, .babelrc.json, package.json#babel) for deprecated presets, plugin conflicts, ordering issues, and b...

Security Scan

The skill is internally consistent: it is an instruction-only validator that reads local Babel config files and reports issues, and its code and SKILL.md match that purpose without requesting extra credentials or performing network/install operations.

Purpose & Capability

Name/description match the included script and runtime instructions. The tool only reads and analyzes Babel config files and reports findings; it does not require unrelated credentials, binaries, or services.

Instruction Scope

SKILL.md instructs running the bundled Python script on local config files. The script only reads the specified file and looks for sibling config files in the same directory (expected for detecting config conflicts). It does not instruct broad data collection or transmission.

Install Mechanism

No install steps are declared and the code is pure Python stdlib. No downloads, package manager installs, or archive extraction are present in the manifest.

Credentials

The skill requests no environment variables, credentials, or config paths. The script reads files the user points it at and sibling files in the same directory—this is proportionate to a config linter.

Persistence & Privilege

Skill is not always-enabled and does not attempt to modify other skills or system configuration. It performs read-only analysis of local files and does not persist credentials or enable itself automatically.

Assessment

This skill appears safe and does what it claims: run the included Python script against Babel config files to get warnings/errors. Before running, ensure you execute it on projects you trust (it will read the target file and other Babel-related files in the same directory). No network calls, installs, or secret access are present, but if you need extra assurance you can open and review scripts/babel_config_validator.py yourself (it uses only the Python stdlib).

Validate babel.config.json, .babelrc, .babelrc.json, and package.json#babel for deprecated presets/plugins, conflicting transforms, ordering issues, and best practices. Supports text, JSON, and summary output formats with CI-friendly exit codes.

Commands

# Full validation (all 24+ rules)
python3 scripts/babel_config_validator.py validate babel.config.json

# Quick syntax-only check (structure rules only)
python3 scripts/babel_config_validator.py check .babelrc

# Explain config in human-readable form
python3 scripts/babel_config_validator.py explain babel.config.json

# Suggest improvements
python3 scripts/babel_config_validator.py suggest package.json

# JSON output (CI-friendly)
python3 scripts/babel_config_validator.py validate .babelrc --format json

# Summary only (pass/fail + counts)
python3 scripts/babel_config_validator.py validate .babelrc --format summary

# Strict mode (warnings become errors)
python3 scripts/babel_config_validator.py validate .babelrc --strict

Rules (24+)

#	Category	Severity	Rule
S1	Structure	Error	File not found or unreadable
S2	Structure	Error	Empty config or no content
S3	Structure	Warning	Both babel.config and .babelrc present (conflict)
S4	Structure	Warning	Unknown top-level config keys
S5	Structure	Error	Invalid JSON syntax
P1	Presets	Error	Deprecated preset (es2015, es2016, es2017, latest, stage-*)
P2	Presets	Warning	Preset ordering matters (@babel/preset-typescript before @babel/preset-env)
P3	Presets	Warning	Duplicate presets
P4	Presets	Error	Unknown/misspelled preset name
P5	Presets	Warning	Missing @babel/preset-env (most configs need it)
L1	Plugins	Error	Deprecated plugin (@babel/plugin-proposal-* → built-in)
L2	Plugins	Warning	Duplicate plugins
L3	Plugins	Warning	Plugin ordering conflict (decorators before class-properties)
L4	Plugins	Warning	Conflicting plugins (transform-runtime + external-helpers)
L5	Plugins	Warning	Plugin without @babel/ scope (may be community or typo)
M1	Modules	Warning	modules: false in preset-env without bundler context
M2	Modules	Warning	sourceType mismatch with modules setting
M3	Modules	Warning	Conflicting module transforms
E1	Env/Overrides	Warning	Empty env config section
E2	Env/Overrides	Warning	Override without test pattern
E3	Env/Overrides	Warning	Unknown env name (not development/production/test)
B1	Best Practices	Warning	loose mode inconsistency across plugins
B2	Best Practices	Warning	Missing targets/browserslist (unoptimized output)
B3	Best Practices	Warning	useBuiltIns without corejs version
B4	Best Practices	Warning	corejs version outdated (< 3)

Output Formats

• text (default): Human-readable with colors and severity icons
• json: Machine-parseable JSON array of findings
• summary: Pass/fail with error/warning counts

Exit Codes

• 0: No errors (warnings only or clean)
• 1: One or more errors found
• 2: File not found or invalid input

Requirements

• Python 3.8+
• No external dependencies (pure stdlib)