Biome Config Validator

Validate biome.json configuration files for correctness, conflicts, deprecated options, and best practices.

Commands

# Validate a biome.json file (all rules)
python3 scripts/biome_config_validator.py lint biome.json

# Check for rule conflicts only
python3 scripts/biome_config_validator.py conflicts biome.json

# Check for deprecated options
python3 scripts/biome_config_validator.py deprecated biome.json

# Validate structure only
python3 scripts/biome_config_validator.py validate biome.json

# JSON output
python3 scripts/biome_config_validator.py lint biome.json --format json

# Summary only
python3 scripts/biome_config_validator.py lint biome.json --format summary

Rules (22)

Structure (5)

• Invalid JSON syntax
• Unknown top-level keys
• Invalid schema version ($schema URL)
• Missing recommended sections (linter, formatter)
• Invalid file patterns in includes/excludes

Linting (7)

• Unknown lint rule names
• Rules in wrong category
• Conflicting rules (e.g., useConst vs noConst)
• Disabled recommended rules without justification
• Invalid rule severity values
• Empty rule groups
• Deprecated rule names

Formatting (5)

• Invalid indent style/width combination
• Conflicting formatter settings
• Line width out of reasonable range
• Invalid quote style values
• Tab width mismatch with indent width

Best Practices (5)

• Missing VCS integration settings
• Overly broad ignore patterns
• No organizeImports configuration
• Missing JavaScript/TypeScript specific settings
• Extends pointing to non-existent config

Output Formats

• text (default): Human-readable with colors and severity icons
• json: Machine-readable with file, rule, severity, message
• summary: Counts by severity only

Exit Codes

• 0: No issues (or warnings only)
• 1: Errors found
• 2: Invalid input