write-openapi

---
name: write-openapi
description: >-
license: MIT
---

# GitBook OpenAPI

GitBook turns an OpenAPI document into interactive, testable API reference blocks. You give it a spec (as JSON or YAML), and it renders endpoints, parameters, schemas, auth, and an in-page request runner. Most of the customization happens inside the spec itself through `x-*` extensions, not in the GitBook UI, so the bulk of any task here is editing OpenAPI YAML correctly.

This skill covers the full surface: getting a spec into GitBook, generating reference pages, structuring navigation, making the "Test it" runner work, controlling how operations and schemas display, and automating updates from CI/CD.

## How you can talk to GitBook

Most of this skill — editing the OpenAPI YAML/JSON itself — is transport-agnostic. But getting a spec *into* GitBook, or generating/inserting reference pages, does touch GitBook, and there's more than one way to do that: GitBook's MCP server and the REST API. Check what's actually available in the current session and prefer **MCP first**: if GitBook MCP tools are already connected, use them for anything they cover (publishing/updating a spec, generating reference pages) instead of making direct API calls. Don't run a detection script for this — you already know your own available tools/MCP connections; just use that awareness.

The steps below are described as outcomes ("add the spec", "generate the reference pages") rather than tied to one transport, so they apply whichever you use. If GitBook MCP tools are connected, call those directly — their own schemas describe their parameters. If you're on the REST API path instead, the exact endpoints and request bodies are in "Add or update a specification" below.

- **GitBook MCP** — a full read/write surface over the same capabilities described below, not a narrower view. If it isn't connected yet and the task is substantial enough to benefit (publishing a new spec, generating a full reference — not a one-off tweak), offer to set it up: `claude mcp add --transport http gitbook-mcp https://mcp.gitbook.com/mcp` (then `/mcp` to complete OAuth sign-in — or append `--header "Authorization: Bearer $GITBOOK_TOKEN"` to skip the browser flow). Codex equivalent: `codex mcp add gitbook-mcp --url https://mcp.gitbook.com/mcp`. Note: this is a different server from GitBook's separate, read-only "published docs" MCP, which only exposes already-published content.
- **REST API** (`https://api.gitbook.com/v1`) — the fallback when MCP isn't connected, or for anything MCP doesn't cover. Needs `GITBOOK_TOKEN` as a bearer header on every request.

The same personal access token (from https://app.gitbook.com/account/developer) works as the bearer token for both. MCP additionally supports OAuth as a friendlier alternative to pasting a token.

**If you end up needing a token** (REST API path, or MCP without OAuth), check for it at the start of the session:

```bash
[ -n "$GITBOOK_TOKEN" ] && echo "Token found" || echo "GITBOOK_TOKEN is not set"
```

If `GITBOOK_TOKEN` is not set, ask the user directly:
1. Tell them they need a GitBook personal access token. Direct them to **https://app.gitbook.com/account/developer** to create one.
2. Ask them to paste the token into the conversation. Immediately export it as an environment variable (`export GITBOOK_TOKEN=<pasted value>`) and don't repeat it back in your response.
3. Do not proceed with any API calls until the token is confirmed present in the environment.

Never write the token to a file, never echo it back in a response, never commit it.

The GitBook CLI's `gitbook openapi publish` command (see "Add or update a specification" below) reaches the same underlying capability as the API and MCP — it's a convenience wrapper, not a separate feature set, and authenticates with the same `GITBOOK_TOKEN`.

## Key facts to know first

These shape almost every decision, so internalize them before editing anything.

- **Supported versions.** GitBook accepts Swagger 2.0 and OpenAPI 3.0 specs. Some features need newer versions: webhooks require OpenAPI 3.1, and the official `parent` tag property requires OpenAPI 3.2+ (use `x-parent` on 3.0.x and 3.1.x). Always check the spec's `openapi:`/`swagger:` version before reaching for a version-gated feature.
- **The "Test it" runner is powered by Scalar.** It runs requests from the reader's browser unless you route them through GitBook's proxy.
- **A spec's source is a file or a URL — and that's what determines updates, not which transport (MCP, API, CLI, or UI) you used to set it.** URL sources auto-refresh every 6 hours; file sources only change when re-uploaded or re-published.
- **`x-*` extensions are namespaced and safe to keep in a shared spec.** Tools that do not understand a given extension ignore it, so a spec instrumented for GitBook still validates and works elsewhere.

## What are you trying to do?

Match the task to the right section. For the deeper reference material, two files live alongside this one:

- Editing or looking up any `x-*` extension, with full YAML for each: read `references/extensions.md`.
- Making the interactive runner work end to end (auth schemes, servers, CORS, proxy): read `references/test-it-setup.md`.

| Task | Go to |
| --- | --- |
| Get a spec into GitBook, or update one | "Add or update a specification" |
| Generate reference pages, or drop a single endpoint/schema into a page | "Insert an API reference" |
| Split, order, nest, title, or icon your pages | "Structure the reference" |
| Make "Test it" work, fix CORS, configure auth | "Configure the Test it runner" + `references/test-it-setup.md` |
| Mark an endpoint experimental, deprecated, or hidden | "Manage operation lifecycle" |
| Look up the exact name/scope of an extension | "Extensions cheat-sheet" + `references/extensions.md` |
| Auto-publish the spec from a pipeline | "Automate with CI/CD" |

## Add or update a specification

A spec must exist in the organization before any block or page can reference it. Adding and updating are the same underlying operation on every transport — pick whichever you have per "How you can talk to GitBook" above. Whichever you use, give the spec a name/slug up front: it's how you reference it later and how you tell multiple specs apart.

**GitBook MCP** — if connected, use its spec tool directly for creating or updating a spec from either a file or a URL; its schema covers both source types.

**REST API** — create with a URL source:

```bash
curl -s -X POST -H "Authorization: Bearer $GITBOOK_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"slug": "<spec-name>", "source": {"url": "<hosted-url>"}}' \
  https://api.gitbook.com/v1/orgs/$ORG_ID/openapi
```

or from a file:

```bash
curl -s -X POST -H "Authorization: Bearer $GITBOOK_TOKEN" \
  -F "slug=<spec-name>" \
  -F "file=@./openapi.yaml" \
  https://api.gitbook.com/v1/orgs/$ORG_ID/openapi
```

Update (replace) an existing spec the same way against `PATCH /v1/orgs/{orgId}/openapi/{specId}`.

**GitBook CLI** — a thin wrapper over the same API call, useful in scripts and pipelines (same command adds or updates; running it against a URL also forces a refresh):

```bash
gitbook openapi publish --spec <spec-name> --organization <organization-id> <path-or-url>
```

For pipeline automation see "Automate with CI/CD". CLI details: https://gitbook.com/docs/developers/integrations/reference

**GitBook app UI** — open the **OpenAPI** section in the sidebar, click **Add specification**, name it, then choose to upload a file or enter a hosted URL. Updating depends on the source: URL sources check every 6 hours automatically (click **Check for updates** to pull immediately; switch File to URL via **Edit** in the breadcrumb actions menu); file sources need **Update** to upload a new version.

## Insert an API reference

Once the spec exists, surface it in the docs one of two ways.

**Generate a full set of pages (recommended for a complete reference).** In the target space's table of contents, click **Add new...** at the bottom, then **OpenAPI Reference**, pick the spec, and insert. GitBook creates one page per tag in the spec (see "Structure the reference"), and optionally a models page listing every schema. These pages keep updating whenever the spec updates.

**Insert a single operation or schema into an existing page.** Press `/`, search for **OpenAPI**, pick the spec, choose **Continue**, then select the specific operations and/or schemas to embed.

**Block syntax.** When writing GitBook markdown directly, an OpenAPI operation block looks like this (the inner line repeats the source):

```
{% openapi src="https://petstore3.swagger.io/api/v3/openapi.json" path="/pet" method="post" %}
https://petstore3.swagger.io/api/v3/openapi.json
{% endopenapi %}
```

To highlight one or more schemas inline (for example inside a tag description), use the schemas block:

```
{% openapi-schemas spec="petstore" schemas="Pet" grouped="false" %}
The Pet object
{% endopenapi-schemas %}
```

## Structure the reference

GitBook builds navigation from the spec's `tags`, so structuring the reference is mostly structuring tags. Full YAML for every extension named here is in `references/extensions.md`.

- **Split operations across pages:** give operations the same tag, and each tag becomes its own page.

  ```yaml
  paths:
    /pet:
      put:
        tags:
          - pet
        summary: Update an existing pet.
        operationId: updatePet
  ```

- **Order pages:** page order follows the order of entries in the top-level `tags` array.

  ```yaml
  tags:
    - name: pet
    - name: store
    - name: user
  ```

- **Nest pages into groups:** use `parent` (OpenAPI 3.2+) or `x-parent` (3.0.x/3.1.x) to point a tag at its parent tag.

  ```yaml
  tags:
    - name: everything
    - name: pet
      x-parent: everything
    - name: store
      x-parent: everything
  ```

  If a parent page has no `description`, GitBook automatically renders a card-based layout linking its sub-pages.

- **Add titles, icons, and descriptions per page** via tag-level extensions. Icons accept any Font Awesome name (https://fontawesome.com/search).

  ```yaml
  tags:
    - name: pet
      x-page-title: Pet              # title in the table of contents and page header
      x-page-icon: dog               # icon in the ToC and next to the title
      x-page-description: Pets are amazing!   # shown just above the title
      description: Everything about your Pets # the page body
  ```

- **Write rich descriptions.** Tag `description` fields accept GitBook markdown, including advanced blocks such as `{% tabs %}`, so a page intro can be far more than plain text.

- **Document webhooks** (OpenAPI 3.1) with a top-level `webhooks` field that mirrors `paths`:

  ```yaml
  openapi: 3.1.0
  webhooks:
    newPet:
      post:
        summary: New pet event
        requestBody:
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Pet"
        responses:
          "200":
            description: Received successfully
  ```

## Configure the Test it runner

The interactive runner only works as well as the spec describes it. The runner targets the URLs in the `servers` array and can only present auth that the spec declares under `components.securitySchemes`. For anything non-trivial (Bearer/JWT, API key, OAuth2, multiple or templated server URLs, per-operation overrides), read `references/test-it-setup.md`, which has copy-paste YAML for each pattern.

Two quick decisions you will hit constantly:

- **"Why isn't my spec loading?" / "Why does Test it fail?" (URL specs).** This is almost always CORS. A URL-added spec requires the API to allow cross-origin GET requests from the docs origin (for example `https://your-site.gitbook.io` or your custom domain). Public, credential-free endpoints can return `Access-Control-Allow-Origin: *`.
- **API can't enable CORS?** Route requests through GitBook's proxy with `x-enable-proxy: true` (at the root for the whole spec, or on a single operation; the operation value wins). The proxy forwards all HTTP methods, headers, cookies, and bodies, but only to URLs listed in `servers`, so make sure every base URL you want to test is in that array. Details in `references/test-it-setup.md`.

To remove the runner from an endpoint (or the whole spec), set `x-hideTryItPanel: true`.

## Manage operation lifecycle

Common when endpoints are not production-ready or are being phased out. All of these are operation-level unless noted.

- **Not stable yet:** `x-stability: experimental` (also `alpha` or `beta`).
- **Deprecated:** `deprecated: true`. Deprecated endpoints show a deprecation warning on the published site.
- **Deprecated with an end date:** add `x-deprecated-sunset: 2030-12-05` (ISO 8601, `YYYY-MM-DD`).
- **Hide an endpoint entirely:** `x-internal: true` (or its alias `x-gitbook-ignore: true`).
- **Hide one response sample:** set `x-hideSample: true` on that response object (for example under `responses.200`).

```yaml
paths:
  /pet:
    put:
      operationId: updatePet
      x-stability: experimental
      deprecated: true
      x-deprecated-sunset: 2030-12-05
```

## Extensions cheat-sheet

Every GitBook-supported extension at a glance. For the full YAML example of any row, open `references/extensions.md`.

| Extension | Purpose | Where it goes |
| --- | --- | --- |
| `x-page-title` / `x-displayName` | Display name of a tag (navigation + page title) | tag |
| `x-page-description` | Short description shown above the page title | tag |
| `x-page-icon` | Font Awesome icon for the page | tag |
| `parent` / `x-parent` | Nest a tag under a parent tag (`parent` = 3.2+, `x-parent` = 3.0.x/3.1.x) | tag |
| `x-hideTryItPanel` | Show or hide the "Test it" runner | root or operation |
| `x-expandAllResponses` | Expand all response sections by default | root or operation |
| `x-expandAllModelSections` | Expand all model/schema sections by default | root or operation |
| `x-enable-proxy` | Route "Test it" requests through GitBook's proxy | root or operation (operation wins) |
| `x-codeSamples` | Provide custom code samples (`lang`, `label`, `source`) | operation |
| `x-enumDescriptions` | Per-value descriptions for an `enum`, rendered as a table | schema |
| `x-internal` / `x-gitbook-ignore` | Hide an endpoint from the reference | operation |
| `x-stability` | Mark `experimental`, `alpha`, or `beta` | operation |
| `deprecated` | Mark an operation deprecated | operation |
| `x-deprecated-sunset` | Sunset date for a deprecated operation (`YYYY-MM-DD`) | operation |
| `x-hideSample` | Hide a single response sample | response object |
| `x-gitbook-prefix` | Custom auth prefix (e.g. `Token`); not allowed on `http` schemes | security scheme |
| `x-gitbook-token-placeholder` | Default token placeholder shown in the runner | security scheme |

Two display extensions worth highlighting because they take a root default that operations can opt out of:

```yaml
openapi: '3.0'
x-expandAllResponses: true        # default for every operation
x-expandAllModelSections: true
paths:
  /pets:
    get:
      x-expandAllResponses: false # opt this one out
```

Custom code samples replace GitBook's auto-generated snippets and accept multiple languages:

```yaml
paths:
  /users:
    get:
      summary: Retrieve users
      x-codeSamples:
        - lang: JavaScript
          label: Node SDK
          source: |
            import { createAPIClient } from 'my-api-sdk';
            const client = createAPIClient({ apiKey: 'my-api-key' });
            client.users.list().then(console.log);
        - lang: cURL
          label: CLI
          source: |
            curl -L -H 'Authorization: Bearer <token>' \
              'https://api.example.com/v1/users'
```

## Automate with CI/CD

Publish the spec from any pipeline with the CLI. Set `GITBOOK_TOKEN` as a secret, then run `openapi publish` against a file (generated during the build) or a URL (forces a refresh after a release).

```bash
export GITBOOK_TOKEN=<api-token>
gitbook openapi publish \
  --spec <spec-name> \
  --organization <organization-id> \
  example.openapi.yaml
```

GitHub Actions example, triggered on spec changes to `main`:

```yaml
name: Publish OpenAPI to GitBook
on:
  push:
    branches: ["main"]
    paths: ["**/*.yaml", "**/*.yml", "**/*.json"]
  workflow_dispatch:
jobs:
  publish:
    runs-on: ubuntu-latest
    env:
      GITBOOK_TOKEN: ${{ secrets.GITBOOK_TOKEN }}
      GITBOOK_SPEC_NAME: ${{ vars.GITBOOK_SPEC_NAME }}
      GITBOOK_ORGANIZATION_ID: ${{ vars.GITBOOK_ORGANIZATION_ID }}
    steps:
      - uses: actions/checkout@v4
      - name: Publish spec to GitBook
        run: |
          npx -y @gitbook/cli@latest openapi publish \
            --spec "$GITBOOK_SPEC_NAME" \
            --organization "$GITBOOK_ORGANIZATION_ID" \
            <path_to_spec>
```