JSON Rules

Below the list of rules supported by Biome, divided by group. Here’s a legend of the emojis:

• The icon indicates that the rule is part of the recommended rules.
• The icon indicates that the rule provides a code action (fix) that is safe to apply.
• The icon indicates that the rule provides a code action (fix) that is unsafe to apply.
• The icon indicates that the rule has been implemented and scheduled for the next release.

nursery

Rule name	Description	Properties
noJsonUnsafeValues	Disallow unsafe JSON values that may cause interoperability issues.
noRestrictedDependencies	Disallow dependencies that are known to have better alternatives.
useConsistentObjectKeys	Enforce JSON keys with consistent Unicode representation.
useConsistentUnicodeBom	Require or disallow a Unicode byte order mark at the beginning of a file.
usePackageJsonCpu	Require the cpu field in package.json.
usePackageJsonEngines	Require the engines field in package.json.
usePackageJsonValidCpu	Require the cpu field in package.json to be a valid list of processor types.
usePackageJsonValidEngines	Enforce that the engines field in package.json is valid.

style

Rule name	Description	Properties
noTopLevelLiterals	Require the JSON top-level value to be an array or object.

suspicious

Rule name	Description	Properties
noBiomeFirstException	Disallow ineffective ordering in files.includes patterns.
noDuplicateDependencies	Disallow duplicate dependencies in package.json.
noDuplicateObjectKeys	Disallow duplicate keys in JSON objects.
noEmptyObjectKeys	Disallow empty keys in JSON objects.
noQuickfixBiome	Disallow quickfix.biome in supported editor settings.
noUntrustedLicenses	Disallow dependencies with untrusted licenses.
useBiomeIgnoreFolder	Prefer folder exclusions that prevent Biome from scanning the folder.
useRequiredScripts	Require configured scripts in package.json.

Recommended rules

• noBiomeFirstException (Severity: error)
• noDuplicateObjectKeys (Severity: error)
• noQuickfixBiome (Severity: information)
• useBiomeIgnoreFolder (Severity: warning)

Missing a rule? Help us by contributing to the analyzer or create a rule suggestion here.