> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nulix.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Nulix Categories: Organize Articles and Shape Navigation

> Learn how Nulix categories group related articles, support two levels of nesting, and shape your knowledge base sidebar navigation.

Categories are the organizational backbone of your Nulix knowledge base. They group related articles under a shared label and appear as expandable sections in the sidebar navigation that readers see when they visit your knowledge base. A well-planned category structure helps readers find answers quickly and signals the overall shape of your documentation at a glance. Before you start publishing articles, it is worth spending a few minutes thinking about which categories you need and how they nest together.

## How Categories Work

When you create a category, Nulix adds it as a top-level section in your knowledge base sidebar. Articles assigned to that category appear as a list beneath it. Readers can expand and collapse categories to browse content without leaving the current page.

Categories also influence **AI Search** relevance. Nulix uses the category name and description as contextual signals when surfacing results, so descriptive category names improve the quality of search answers.

## Nested Categories

Nulix supports **two levels of nesting**: top-level categories and sub-categories. This gives you enough hierarchy to separate broad topics without creating a navigation tree so deep that readers get lost.

```text theme={null}
Getting Started          ← Top-level category
├── Quickstart Guide     ← Article
├── Account Setup        ← Article
└── Initial Configuration  ← Sub-category
    ├── SSO Setup        ← Article
    └── API Keys         ← Article
```

> [!NOTE]
>
> Nulix does not support a third level of nesting. If you find yourself wanting sub-sub-categories, consider whether you need a separate knowledge base or whether tags can provide the extra granularity instead.

## Category Properties

Configure the following properties for each category from the **Content → Categories** panel in your knowledge base editor:

| Property | Description |
| - | - |
| **Name** | The label displayed in the sidebar and used as the page heading when a reader clicks the category. |
| **Description** | Optional text shown on the category landing page and used by AI Search for context. |
| **Icon** | An emoji or icon from the Nulix icon library displayed next to the category name in the sidebar. |
| **Slug** | The URL-safe path segment for the category page (e.g., `getting-started`). |
| **Sort order** | Controls the position of this category relative to its siblings — drag to reorder or set an explicit integer. |
| **Visibility** | Optionally restrict the entire category (and all its articles) to a specific audience. |

## Best Practices

> [!TIP]
>
> Keep your **top-level categories broad and immediately recognizable**. Labels like "Getting Started", "Billing", "Troubleshooting", and "API Reference" set clear reader expectations. Reserve sub-categories for situations where a top-level category grows beyond seven or eight articles.

A few additional guidelines that improve reader experience:

* **Limit top-level categories to eight or fewer.** A crowded sidebar overwhelms readers on first visit.
* **Use nouns, not verbs, for category names.** "Billing" is easier to scan than "Managing Your Billing".
* **Write a short description for every category.** Even two sentences improve AI Search quality and the category landing page.
* **Review sort order periodically.** Move high-traffic categories toward the top so new readers find the most important content first.

## Next Steps

> **[Organizing Content](https://docs.nulix.io/publishing/organizing-content.md)**
>
> Learn how to create categories, assign articles, manage sort order, and restructure your knowledge base as it grows.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.