# MD074 - MkDocs nav validation
Aliases: `mkdocs-nav`
## What this rule does
Validates that MkDocs navigation entries in `mkdocs.yml` point to existing files. This rule only runs when the markdown flavor is set to `mkdocs`.
## Why this matters
- **Prevents broken navigation**: Ensures all nav entries resolve to actual documentation files
- **Catches typos**: Common mistakes in file paths are caught before deployment
- **Maintains site structure**: Helps keep your MkDocs site organized and complete
## Examples
Given this `mkdocs.yml`:
```yaml
site_name: My Docs
docs_dir: docs
nav:
- Home: index.md
- Guide: guide.md
- API:
- Overview: api/overview.md
- Reference: api/reference.md
```
### ✅ Correct
All referenced files exist in the `docs/` directory:
- `docs/index.md`
- `docs/guide.md`
- `docs/api/overview.md`
- `docs/api/reference.md`
Directory nav entries like `- Section: section/` are valid if `section/index.md` exists.
### ❌ Incorrect
```yaml
nav:
- Home: index.md
- Guide: missing-guide.md # File doesn't exist
- API:
- Overview: /api/overview.md # Absolute path (if configured to warn)
```
### 🔧 Fixed
This rule cannot automatically fix broken nav entries. You must manually:
- Fix typos in file paths
- Create missing documentation files
- Update nav structure after moving files
## Configuration
### `not-found`
How to handle nav entries pointing to non-existent files.
| `warn` (default) | Report a warning |
| `ignore` | Skip validation |
### `omitted-files`
How to handle files in `docs_dir` that aren't referenced in nav.
| `warn` | Report files not in nav |
| `ignore` (default) | Skip this check |
### `absolute-links`
How to handle absolute links (starting with `/`) in nav entries.
| `warn` | Report a warning |
| `ignore` (default) | Skip validation |
### Example configuration
```toml
# .rumdl.toml
[global]
flavor = "mkdocs"
[MD074]
not-found = "warn"
omitted-files = "warn"
absolute-links = "warn"
```
## Automatic fixes
This rule does not provide automatic fixes. Missing nav entries must be corrected manually.
## Learn more
- [MkDocs Navigation](https://www.mkdocs.org/user-guide/writing-your-docs/#configure-pages-and-navigation)
- [MkDocs Configuration](https://www.mkdocs.org/user-guide/configuration/)
## Related rules
- [MD057 - Check that file links work](md057.md)
- [MD051 - Fix broken link fragments](md051.md)