About

Flint’s Markdown plugin supports linting .md source code. It comes provided with the flint npm package.

Presets

Flint’s Markdown plugin provides the following presets:

Preset	Recommended	Description
logical	✅ Always	Common rules for finding bugs and enforcing good logical practices in Markdown files.
logicalStrict	☑️ When Ready	Additional rules for finding bugs and enforcing good logical practices in Markdown files.
stylistic	✅ Always	Common rules for consistent styling and best stylistic practices in Markdown files.
stylisticStrict	☑️ When Ready	Additional rules for consistent styling and best stylistic practices in Markdown files.

If you are just getting started with linting, Flint recommends using the logical and stylistic presets:

flint.config.ts

import { defineConfig, md } from "flint";

export default defineConfig({
  use: [
    {
      files: md.files.all,
      rules: [md.presets.logical, md.presets.stylistic],
    },
  ],
});

If you are experienced with both Markdown and linting, Flint recommends using the logicalStrict and stylisticStrict presets:

flint.config.ts

import { defineConfig, md } from "flint";

export default defineConfig({
  use: [
    {
      files: md.files.all,
      rules: [md.presets.logicalStrict, md.presets.stylisticStrict],
    },
  ],
});

Note

Coming soon: more expansive documentation on choosing and combining plugins & presets with Flint.

logical

Rules that find bugs and enforce good Markdown practices for most-to-all Markdown files.

flint.config.ts

import { defineConfig, md } from "flint";

export default defineConfig({
  use: [
    {
      files: md.files.all,
      rules: md.presets.logical,
    },
  ],
});

logicalStrict

Additional logical rules that enforce best practices which are not always straightforward to implement. These rules are recommended for projects where a majority of developers are experienced with both Markdown and using a linter.

flint.config.ts

import { defineConfig, md } from "flint";

export default defineConfig({
  use: [
    {
      files: md.files.all,
      rules: md.presets.logicalStrict,
    },
  ],
});

This preset’s rules are a superset of those in logical.

stylistic

Rules that enforce consistent styling and best stylistic practices for most-to-all Markdown files.

flint.config.ts

import { defineConfig, md } from "flint";

export default defineConfig({
  use: [
    {
      files: md.files.all,
      rules: md.presets.stylistic,
    },
  ],
});

stylisticStrict

Additional stylistic rules that enforce best practices which are not always straightforward to implement. These rules are recommended for projects where a majority of developers are experienced with both Markdown and using a linter.

flint.config.ts

import { defineConfig, md } from "flint";

export default defineConfig({
  use: [
    {
      files: md.files.all,
      rules: md.presets.stylisticStrict,
    },
  ],
});

This preset’s rules are a superset of those in stylistic.

Rules

Implemented: 5 of 17 (29.4%)

Flint Name	Preset	Biome Rule(s)	Deno Lint Rule(s)	ESLint Rule(s)	Oxlint Rule(s)
definitionContents	Logical			markdown/no-empty-definitions
definitionDuplicates	Logical			markdown/no-duplicate-definitions
definitionUses	Logical			markdown/no-unused-definitions
headingIncrements	Logical			markdown/heading-increment
imageAltTexts	Logical			markdown/require-alt-text
imageContents	Logical			markdown/no-empty-images
labelReferences	Logical			markdown/no-missing-label-refs
labelReferenceValidity	Logical			markdown/no-invalid-label-refs
linkContents	Logical			markdown/no-empty-links
linkFragments	Logical			markdown/no-missing-link-fragments
referenceLikeUrls	Logical			markdown/no-reference-like-url
tableColumnCounts	Logical			markdown/table-column-count
headingsRootDuplicates	Logical (Strict)			markdown/no-multiple-h1
mediaSyntaxReversals	Stylistic			markdown/no-reversed-media-syntax
bareUrls	Stylistic (Strict)			markdown/no-bare-urls
fencedCodeLanguages	Stylistic (Strict)			markdown/fenced-code-language
headingDuplicates	Stylistic (Strict)			markdown/no-duplicate-headings

Selectors

Flint’s Markdown plugin provides the following file selector:

• all: **/*.md