ESLint plugins: markdownlint

Even if you don't write code, you still encounter Markdown — in documentation, README files, or articles. It's simpler than HTML and more reliable than Word: an unclosed tag won't break the layout, and adding a hyphen won't send the entire paragraph into another dimension. But if the texts are bulky, they may quickly accumulate stylistic errors and inconsistencies: extra spaces, incorrect heading styles, list numbering, and so on. It's a minor issue, but fixing it will make the text much easier to read.

eslint-plugin-markdownlint helps highlight such errors: it integrates Markdown file checking directly into ESLint using markdownlint rules.

Installation

npm install --save-dev eslint-plugin-markdownlint

// eslint.config.js
import markdownlintPlugin from "eslint-plugin-markdownlint";
import markdownlintParser from "eslint-plugin-markdownlint/parser.js";

const markdownlintPluginConfig = {
  files: ["*.md", "*.mdx"],
  plugins: { markdownlint: markdownlintPlugin },
  languageOptions: { parser: markdownlintParser },
  rules: markdownlintPlugin.configs.recommended.rules
};

export default [
  // ...
  markdownlintPluginConfig
];

Features

• The plugin supports checking .mdx files.
• Uses ESLint environment — no need to install additional libraries.
• Most rules support autofix via --fix.
• You can adapt any rules to your needs or disable unnecessary ones.

What exactly does it check?

The basic rules cover the most common errors and inconsistencies:

• Headings: MD001, MD003, MD018, MD025 — styles, indents, nesting.
• Lists and blocks: MD004, MD005, MD007, MD030, MD032.
• Indents, spaces, and line breaks: MD009, MD010, MD012, MD047.
• Code and links: MD014, MD040, MD042, MD052.
• General stylistic rules: MD026 (period in the title), MD036 (italics instead of a title), MD041 (H1 — first line).
• Table layout and inline HTML: MD033, MD055, MD058

Full list of rules.

Summary

If your Markdown project already uses ESLint, add this plugin and write clean texts without getting distracted by stylistic edits.