---

name: editorconfig-config description: EditorConfig file validation and template for enforcing consistent coding styles across editors and IDEs in monorepos. Includes 4 required standards (root declaration, universal settings with UTF-8 and LF line endings, language-specific indentation for JS/TS/Markdown/Python, root-only placement in monorepos). Use when creating or auditing .editorconfig files to ensure consistent code formatting.

EditorConfig Configuration Skill

This skill provides .editorconfig template and validation logic for maintaining consistent coding styles across editors and IDEs.

Purpose

Manage .editorconfig configuration to:

• Enforce consistent character encoding and line endings
• Define language-specific indentation rules
• Preserve trailing whitespace where needed (Markdown)
• Ensure monorepo consistency with single root configuration

Usage

This skill is invoked by the editorconfig-agent when:

• Creating new .editorconfig files
• Auditing existing EditorConfig configurations
• Validating EditorConfig files against standards

Template

The standard EditorConfig template is located at:

templates/.editorconfig.template

The 4 EditorConfig Standards

Rule 1: Root Declaration

File must start with root declaration:

root = true

This stops EditorConfig from searching parent directories, ensuring the monorepo has a single source of truth.

Rule 2: Universal Settings

Must include [*] section with these four settings:

[*]
charset = utf-8
end_of_line = lf
insert_final_newline = true
trim_trailing_whitespace = true

These settings apply to all files unless overridden by language-specific rules.

Rule 3: Language-Specific Indentation

Must include sections for JavaScript/TypeScript (2 spaces), Markdown (preserve trailing), and Python (4 spaces):

[*.{js,jsx,ts,tsx,json,jsonc,yml,yaml}]
indent_style = space
indent_size = 2

[*.md]
trim_trailing_whitespace = false

[*.py]
indent_style = space
indent_size = 4

Rule 4: Root Location Only

In monorepos, .editorconfig must exist ONLY at repository root:

• Place at monorepo root (alongside pnpm-workspace.yaml)
• Individual packages must NOT have their own .editorconfig files
• Single configuration ensures consistency across all packages

Validation

Validation steps:

1. Check file exists at repository root
2. Verify root declaration is present
3. Check universal settings section [*] with all 4 settings
4. Verify language-specific sections exist (JS/TS, Markdown, Python)
5. Scan for package-level .editorconfig files (monorepo only)
6. Report violations

Validation Logic

// Rule 1: Root declaration
if (!content.includes("root = true")) {
  errors.push("Rule 1: Missing 'root = true' declaration");
}

// Rule 2: Universal settings (check all 4)
[
  "[*]",
  "charset = utf-8",
  "end_of_line = lf",
  "insert_final_newline = true",
  "trim_trailing_whitespace = true",
].forEach((setting) => {
  if (!content.includes(setting)) errors.push(`Rule 2: Missing ${setting}`);
});

// Rule 3: Language sections
if (!/\[\*\.\{[^}]*js[^}]*\}\]/.test(content)) {
  errors.push("Rule 3: Missing JS/TS indentation rules");
}
if (!/\[\*\.md\]/.test(content)) {
  errors.push("Rule 3: Missing Markdown section");
}
if (!/\[\*\.py\]/.test(content)) {
  errors.push("Rule 3: Missing Python section");
}

// Rule 4: Package-level configs (monorepo only)
const packageConfigs = glob("packages/**/.editorconfig");
if (packageConfigs.length > 0) {
  errors.push(
    `Rule 4: Remove package-level configs: ${packageConfigs.join(", ")}`,
  );
}

Exception Declaration

Repos may declare exceptions in package.json:

{
  "metasaver": {
    "exceptions": {
      "editorconfig-config": {
        "type": "custom-language-rules",
        "reason": "Requires 4-space indentation for legacy YAML files"
      }
    }
  }
}

Best Practices

1. Place .editorconfig at repository root (monorepo or standalone)
2. Use template as starting point
3. Preserve Markdown trailing whitespace (for double-space line breaks)
4. Add language-specific rules as needed (follow template pattern)
5. Re-audit after making changes

Integration

This skill integrates with:

• Repository type provided via scope parameter. If not provided, use /skill scope-check
• /skill audit-workflow - Bi-directional comparison workflow
• /skill remediation-options - Conform/Update/Ignore choices
• prettier-agent - Coordination with Prettier formatting rules
• eslint-agent - Coordination with ESLint style rules