Generate your API Reference | Fern Documentation

A key benefit of using Fern Docs is that once you’ve defined your API, you get your API Reference documentation with just one line. Add - api: API Reference to your navigation in docs.yml and Fern takes care of the rest! You’ll see your endpoints, types, and cURL snippets automatically populated from your OpenAPI Specification or Fern Definition.

Example:

docs.yml

1 navigation:
2   - api: API Reference

API Reference configuration options

Property	Value
`api` (required)	Title of the API Reference Section
`api-name`	Name of the API we are referencing, if there are multiple APIs
`audiences`	List of audiences that determines which endpoints, schemas, and properties are displayed in your API Reference
`availability`	Set the availability status for the entire API Reference or specific sections
`display-errors`	Displays error schemas in the API References
`snippets`	Enable generated SDK code snippets in your API Reference
`summary`	Relative path to the Markdown file; the summary is displayed at the top of the API section
`layout`	Customize the order that your API endpoints are displayed in the docs site
`icon`	Icon to display next to the API section in the navigation
`slug`	Customize the slug for the API section (by default, the slug is generated from the API title)
`skip-slug`	When `true`, skips the slug generation for the API section
`alphabetized`	When `true`, organizes all sections and endpoints in alphabetical order
`flattened`	Display all endpoints at the top level (hides the API Reference Section’s title)
`paginated`	Display all endpoints on separate pages (by default, endpoints are displayed on one single, long page)

More on customizing your API Reference here.

Include more than one API Reference

To include multiple, distinct API definitions in your documentation, you can indicate which to include using the api-name property. The api-name corresponds to the name of the folder where your API definition is housed.

For example, your file structure might look like this:

$ fern/
>   ├─ fern.config.json 
>   ├─ docs.yml
>   ├─ plant-api/         
>   │   └─ api.yml     # API definition
>   └─ garden-api/          
>       └─ api.yml    # API definition

For a simple setup without tabs, you can include multiple API references directly in your navigation:

docs.yml

1 navigation:
2   - api: Plant Store
3     api-name: plant-api   # Matches folder name containing your API definition
4   - api: Garden
5     api-name: garden-api  # Matches folder name containing your API definition

When using tabs, each API reference must be placed within a tab’s layout:

docs.yml

1 tabs:
2   plant-api:
3     display-name: Plant Store API
4     icon: leaf
5   garden-api:
6     display-name: Garden API
7     icon: tree
8 navigation:
9   - tab: plant-api  # References the tab defined above
10     layout:
11       - api: Plant Store API
12         api-name: plant-api  # Matches folder name containing your API definition
13         skip-slug: true
14   - tab: garden-api  # References the tab defined above
15     layout:
16       - api: Garden API
17         api-name: garden-api  # Matches folder name containing your API definition
18         skip-slug: true