Design Engine API

https://ai.extendify.com/api/design

Generate full WordPress website previews from a text description.

Typical flow

1. Client calls GET /api/design?description=A+bakery+in+Paris&language=fr_FR
   with header: Authorization: Bearer YOUR_TOKEN
2. Gets back { "id": "abc123" }
3. Loads <iframe src="/api/design/abc123/iframe">
4. Iframe shows spinner, then streams final HTML when ready
5. Optionally poll GET /api/design/abc123 for structured data
6. Redirect user to WordPress: /wp-admin/?auto-launch=true&build-id=abc123

Authentication

All requests to GET /api/design require an authentication token sent as a Bearer header:

Authorization: Bearer YOUR_TOKEN

Getting a token: tokens are issued manually by the Extendify team. Reach out to us to get one for your integration.

The token identifies the partner and is used for usage tracking. Read endpoints (GET /api/design/{id}, GET /api/design/{id}/iframe) are unauthenticated — the build ID itself acts as the access credential.

Errors

401 Unauthorized — missing, invalid, or revoked token

Endpoints

`GET /api/design?description=...&language=...`

Starts a new design preview generation.

Param	Required	Default	Description
`description`	Yes	—	What the site is about (e.g. "A bakery in Paris")
`language`	No	`en_US`	WordPress locale code (see supported languages below)

Response 200

{ "id": "abc123" }

Errors

400 — Missing description or unsupported language (returns { error, supported })
429 — Rate limited

Generation runs asynchronously. Use the ID to poll status or load the iframe.

`GET /api/design/{id}/iframe`

Renders the preview as a streamable HTML page. Designed to be loaded in an <iframe>.

Param	Required	Default	Description
`loader-color`	No	`#9ca3af`	CSS color for the loading spinner

Shows an animated loader while generation is in progress
Streams the final HTML once complete
Times out after ~5 minutes
Posts message events to the parent window (works cross-origin)

Parent window events — listen with window.addEventListener('message', handler):

`event`	`height`	Description
`loading`	—	Loader is showing, generation in progress
`ready`	`number`	Final HTML rendered, includes content height
`resize`	`number`	Content height changed (via ResizeObserver)
`error`	—	Generation failed
`timeout`	—	Generation timed out

All messages have { type: 'extendify-design-preview', event, height? }.

`GET /api/design/{id}`

Returns the current state of a design preview.

Response 200

{
  "id": "abc123",
  "status": "complete",
  "html": "<!DOCTYPE html>...",
  "error": null
}

status is complete when the preview is ready, error on failure, or anything else while generation is in progress.

The response also includes additional fields consumed server-side by the WordPress redirect flow. Their shape is internal — don't rely on it.

WordPress redirect

Once the user is happy with the preview, redirect them to their WordPress admin to apply the design:

https://{user-site}/wp-admin/?auto-launch=true&build-id={id}

Param	Description
`auto-launch`	Must be `true` — triggers the Extendify launch flow on page load
`build-id`	The design preview ID returned from `/api/design`

Supported languages

See extendify.com/documentation/supported-languages