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Updating site navigation and TOC files

The table of contents is the list of documents that is displayed on the left side of every page on It is represented by a hierarchical set of _toc.yaml files. The top level _toc.yaml file is _toc.yaml.

If you add a new document to, or if you move existing documentation within the site, you need to change the site navigation, defined in _toc.yaml files. These files are located in the same directory of the documentation file or in a parent directory.

Existing document

To change the documentation navigation for an existing document:

  1. Locate the corresponding _toc.yaml file for the document in the source code tree.

    For example, if you want to modify the navigation for the concepts page of Zircon, you can see that there is a _toc.yaml file in the same directory.

  2. Edit the _toc.yaml file. You have to specify the published location of the document in the _toc.yaml files instead of the actual path in the Fuchsia source code. See _toc.yaml reference.

New document

To add navigation for a new document:

  1. Locate the closest _toc.yaml file for the document. If the directory where you created the document has a _toc.yaml file, use that file. If not, navigate through the parent directories until you locate the closest _toc.yaml file.

  2. Edit the _toc.yaml file. See _toc.yaml reference.

_toc.yaml reference

A _toc.yaml file can contain single entries or expandable sections with multiple entries:

  • Single entry

    A single entry in the table of contents navigation is represented by a title and a path in the corresponding _toc.yaml file. Each entry must also use the correct indentation like the other entries in _toc.yaml.

    Paths must follow these requirements:

    • Paths to files should be the full path from the root of the project. For example, /docs/development/api/
    • Paths to directories should not include a trailing slash, and the directory must have a file named

    For example, to add an entry for the Zircon page in its respective _toc.yaml, you should add an entry:

    - title: "Kernel concepts"
      path: /docs/concepts/kernel/
  • Expandable section

    An expandable section is an expandable group of multiple entries in a table of contents. For example, see the expandable sections, such as Networking and Graphics, in the Concepts section. Each expandable section has an arrow to the left of the section name.

    You can create a group of entries with a section element. Each section must also use the correct indentation like the other entries in _toc.yaml. Then, you can add single entries to the section.

    For example, to add a section in the "System" table of contents _toc.yaml, add a section group and its corresponding entries. Usually the entries are included from another _toc.yaml file:

    - title: "Zircon kernel"
      - include: /docs/concepts/kernel/_toc.yaml

Once you have made these changes, you can submit your changes for review.