Overview

API documentation turns your OpenAPI spec into an API reference in your Help Center: a tab of endpoint pages next to your articles, with request examples, a Try it playground, and a version switcher.

You need an OpenAPI 3.0 or 3.1 spec in JSON or YAML and the Manage Help Center permission. You manage everything under Settings → Help Center → API reference.

What readers get

Endpoint pages

Every endpoint in your spec gets its own page in the API reference tab, grouped by the spec's tags. Each page shows the endpoint's description, parameters, request body, and responses with their schemas. Readers also find endpoint pages through Help Center search, next to your articles.

Request examples and Try it

Each endpoint page shows a request example with a language switcher. You can offer nine languages: cURL, JavaScript, Python, PHP, Go, Java, Ruby, C#, and TypeScript.

With Try it, readers send a test request to your API from the page and see the response. For each version, you choose whether Try it sends requests, shows samples only, or is off, as described in Code samples and the API playground.

Versions and multiple APIs

Each spec you import is one version of your API. When two or more versions are published, readers switch between them at the top of the API reference sidebar. You choose the default version that readers see first, and you can deprecate or archive old versions, as described in Managing API versions and multiple APIs.

You can also publish more than one API in one Help Center, such as a Core API and a separate Payments API. Each API has its own versions, default version, and tab in your top bar.

AI-ready pages and Fibi

Endpoint pages have a page actions menu, like articles. Readers can copy or view a page as Markdown and download the spec, and on public pages they can open it in ChatGPT or Claude. By default, your Help Center's llms.txt lists the endpoint pages of each API's default version, as described in Making your Help Center readable for AI tools.

When Fibi AI Agent uses your Help Center as a knowledge source, it can answer API questions from the published endpoints of each API's default version and link to the endpoint pages.

Guides beside the endpoints

The API reference tab can also hold regular Help Center articles, such as an authentication guide or a quickstart, above the generated endpoint pages. Organizing the API reference tab shows how to add them and where to place the tab in your top bar.

To document an endpoint without a spec, use the API blocks in a regular article, as described in the Help Center block library.

How publishing works

1. Import: Upload a file, link a public URL, or push the spec from your CI pipeline. Publishing an API reference from an OpenAPI spec walks through the first import

2. Review: The import arrives as a draft. Check its endpoints, changes, and warnings before readers see anything

3. Publish: The endpoint pages go live in your Help Center

4. Update: Featurebase checks a linked URL every 6 hours, and your pipeline can push each new version. Each change arrives as a new draft, unless you let CI pushes publish without review, as described in Updating your API reference from a URL or CI

5. Roll back: Make an earlier revision live again if a published change was wrong. Reviewing and publishing API changes covers drafts and rollbacks

Plans and limits

API documentation is available on every plan. On the Free plan, each Help Center can have three APIs with two live versions per API, Try it is available under fair use, and pages show Featurebase branding. Growth and higher plans have no plan limit on APIs or versions.