SHAD0006Use known design-system classes

Why it happens

Misspelled or unsupported class names generate no CSS. Without a resolvable Tailwind theme, the Rule uses a reduced fallback that includes bundled utility names plus discovered @utility names and CSS class selectors, as in the example below. That fallback cannot validate theme tokens or provide spelling suggestions.

Fix

Correct the class name or declare the intended utility in the theme. Allow external stylesheet classes by exact name only when the application loads their CSS.

Example

Correct a utility name using the fallback grammar

Before

<div className="flex-cols" />

After

<div className="flex-col" />

Verify the fix

Run only this rule after editing so the report stays focused on the diagnostic you are closing:

pnpm vite-doctor . --extends shadcn/strict --rules shadcn/no-unknown-classes

Useful links

• Upstream docs

Related rule

• shadcn/no-unknown-classes