# Create a branding preview link

`POST /v1/branding:preview-link` · permission `branding:write`

Creates a link that shows the hosted login page with the environment's current branding drafts, before they are published. The page always draws the latest drafts: change a draft and reload the page to see it. A banner marks the page as a preview and every sign-in control is turned off. Draft text overrides are shown in the page's language; they cannot change the preview banner.

The link is valid for 10 minutes and cannot be revoked; after that it returns `404`. Anyone who has the link can see the draft, so share it only with the people who review the design. An environment can have at most 20 valid links at the same time.

## Request

The body is optional. Without a body the page shows the environment draft only.

| Field | Type | Required | Description |
|---|---|---|---|
| `application_id` | string | no | Also apply this application's draft (`app_…`). |
| `org_id` | string | no | Also apply this organization's draft (`org_…`): its logo and primary color. |

## Response

`200 OK`. The `url` is returned only in this response, with `Cache-Control: no-store`. A request repeated with the same `Idempotency-Key` returns no `url` and `secret_redacted: true`; create a new link instead.

```json
{
  "url": "https://acme.eu1.keenauth.app/u/preview?token=…",
  "expires_at": "2026-10-19T12:10:00Z"
}
```

## Errors

| HTTP | code | When |
|---|---|---|
| 400 | `unknown_field` | The body has an unknown field or is not a JSON object. |
| 404 | `not_found` | The application does not exist in this environment. |
| 422 | `validation_failed` | `application_id` or `org_id` is not a valid ID (`invalid_value`). |
| 401 | `unauthenticated` | The credential is missing, invalid or revoked. |
| 403 | `insufficient_permissions` | The credential lacks the required permission. |
| 429 | `rate_limited` | The environment already has 20 valid links, or the rate limit was exceeded; retry after the `Retry-After` period. |
| 503 | `service_unavailable` | A dependency is temporarily unavailable; retry after the `Retry-After` period. |

## Example

```bash
curl -X POST https://api.eu.keenauth.com/v1/branding:preview-link \
  -H "Authorization: Bearer $KEENAUTH_SECRET_KEY" \
  -H "Content-Type: application/json" \
  -d '{"application_id":"app_01jb…"}'
```

With the CLI:

```bash
keenauth branding preview-link --application-id app_01jb…
```