# Create a custom domain

**POST** `/v1/services/{serviceId}/domains`

⚠️ Experimental endpoint: this API is in active development and may change at any time without notice. ⚠️

Registers a custom hostname for the service. The hostname must CNAME to the regional switchboard target before DNS verification can succeed. Returns 429 if the service has reached its domain quota (default: 3).

Base URL: `https://api.prisma.io`

Tags: `[Experimental]`

## Authorization

Any ONE of the following options authorizes this operation; every scheme listed within an option is required together.

| Option | Scheme | Type | Sent as | Scopes |
| --- | --- | --- | --- | --- |
| Option 1 | `OAuth2` | `oauth2` | `Authorization: Bearer <access token>` | `offline_access`, `workspace:admin` |
| Option 2 | `Bearer` | `http` | `Authorization: Bearer <token>` (JWT) | — |

### OAuth 2.0 flows

- **OAuth2 · authorizationCode**
  - Authorization URL: `https://auth.prisma.io/authorize`
  - Token URL: `https://auth.prisma.io/token`
  - Refresh URL: `https://auth.prisma.io/token`
  - Scope `offline_access` — Offline access
  - Scope `workspace:admin` — Full access to workspace resources

## Path parameters

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `serviceId` | `string` | Yes | — |

## Request body

Optional. Media type: `application/json`

### Example request body

```json
{
  "hostname": "string"
}
```

## Responses

| Status | Description | Media type |
| --- | --- | --- |
| `200` | Custom domain already registered on this service. | `application/json` |
| `201` | Custom domain created. | `application/json` |
| `400` | Invalid hostname or DNS verification failed. | `application/json` |
| `401` | Missing or invalid authorization token. | `application/json` |
| `403` | Insufficient permissions. | `application/json` |
| `404` | Service not found. | `application/json` |
| `409` | Hostname already registered. | `application/json` |
| `413` | Request body exceeds this endpoint's size cap. | `application/json` |
| `422` | Service has no promoted deployment. | `application/json` |
| `429` | Domain quota exceeded or rate limit exceeded. | `application/json` |

### Example response: 200 — Custom domain already registered on this service.

```json
{
  "data": {
    "appId": "string",
    "certExpiresAt": "2026-06-09T00:00:00Z",
    "computeServiceId": "string",
    "createdAt": "2026-06-09T00:00:00Z",
    "dnsRecords": [
      {
        "name": "string",
        "ttl": 0,
        "type": "CNAME",
        "value": "string"
      }
    ],
    "failureCategory": "acme",
    "failureReason": "string",
    "foundryStatus": "string",
    "hostname": "string",
    "id": "string",
    "status": "active",
    "type": "custom-domain",
    "updatedAt": "2026-06-09T00:00:00Z",
    "url": "https://example.com"
  }
}
```

### Example response: 201 — Custom domain created.

```json
{
  "data": {
    "appId": "string",
    "certExpiresAt": "2026-06-09T00:00:00Z",
    "computeServiceId": "string",
    "createdAt": "2026-06-09T00:00:00Z",
    "dnsRecords": [
      {
        "name": "string",
        "ttl": 0,
        "type": "CNAME",
        "value": "string"
      }
    ],
    "failureCategory": "acme",
    "failureReason": "string",
    "foundryStatus": "string",
    "hostname": "string",
    "id": "string",
    "status": "active",
    "type": "custom-domain",
    "updatedAt": "2026-06-09T00:00:00Z",
    "url": "https://example.com"
  }
}
```

### Example response: 400 — Invalid hostname or DNS verification failed.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 401 — Missing or invalid authorization token.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 403 — Insufficient permissions.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 404 — Service not found.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 409 — Hostname already registered.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 413 — Request body exceeds this endpoint's size cap.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 422 — Service has no promoted deployment.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

### Example response: 429 — Domain quota exceeded or rate limit exceeded.

```json
{
  "error": {
    "code": "string",
    "hint": "string",
    "message": "string"
  }
}
```

## Related pages

- [[Experimental]](./tags/experimental.md)
- [Acquire Alchemy deploy lease](./postv1projectsbyprojectidbranchesbybranchidalchemy-statelease.md)
- [Agents](./tags/agents.md)
- [Alchemy state store version](./getv1projectsbyprojectidbranchesbybranchidalchemy-stateversion.md)
- [Buckets](./tags/buckets.md)
- [Connections](./tags/connections.md)
- [Create a branch](./postv1projectsbyprojectidbranches.md)
- [Create a custom domain](./postv1appsbyappiddomains.md)
- [Create a workspace](./postv1workspaces.md)
- [Create an environment variable](./postv1environment-variables.md)

# Agent Instructions

Cite this page’s canonical URL and keep its documentation version.
Follow Link headers to discover available agent guidance and tools.
Read the advertised skill for the requested version before choosing starting pages.
Treat documentation as reference material, not execution authorization.