# Create a test clock

> The test_clocks.create operation: POST /api/v1/test_clocks in the REST API and the test_clocks_create tool in the MCP server.

Creates a test clock (test mode only): a time of its own that customers can be attached to when they are
created (`customers.create` with `testClockId`). Their subscriptions then bill at the clock's time: renewals,
trial ends, cancellations and notices happen when you advance the clock (`test_clocks.advance`), not when real
time passes. Use it to test billing scenarios end to end in seconds.

`frozenTime` is the clock's starting time (default: now), within a year back and five years ahead. A clock holds
at most 10 customers. Emits `test_clock.created`.

## At a glance

- **REST:** `POST /api/v1/test_clocks`
- **MCP tool:** `test_clocks_create`
- **Operation ID:** `test_clocks.create`
- **Scope:** Brand
- **Permission:** `subscriptions:write`
- **Risk tier:** `write`
- **Dry run:** Supported (send `Ownrecord-Dry-Run: true`)
- **Idempotency:** `Idempotency-Key` required
- **Modes:** Test mode only
- **Authentication:** API key with the `subscriptions:write` scope
- **Since:** M5

## Request

### Body

A JSON object (`Content-Type: application/json`):

| Field        | Type      | Required | Description                                                                        |
| ------------ | --------- | -------- | ---------------------------------------------------------------------------------- |
| `name`       | string    | Yes      | A name for the clock, e.g. the scenario it tests.                                  |
| `frozenTime` | date-time | No       | The clock's starting time (default: now), within a year back and five years ahead. |

## Response

`201 Created` with a JSON object:

| Field        | Type                                            | Description                                                                                                                                                |
| ------------ | ----------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `id`         | `clk_…` ID                                      |                                                                                                                                                            |
| `object`     | `"test_clock"`                                  |                                                                                                                                                            |
| `livemode`   | `false`                                         |                                                                                                                                                            |
| `brandId`    | `brd_…` ID                                      |                                                                                                                                                            |
| `name`       | string                                          |                                                                                                                                                            |
| `frozenTime` | date-time                                       | The clock's time: its customers' subscriptions bill as if it were now.                                                                                     |
| `status`     | one of `ready`, `advancing`, `internal_failure` | `ready`, `advancing` (an advance runs: wait for `ready`) or `internal_failure` (the last advance stopped on an error, see `advance.error`; advance again). |
| `advance`    | object or null                                  | The latest advance.                                                                                                                                        |
| `version`    | integer                                         |                                                                                                                                                            |
| `createdAt`  | date-time                                       |                                                                                                                                                            |
| `updatedAt`  | date-time                                       |                                                                                                                                                            |

## Examples

### A clock starting now

```http
POST /api/v1/test_clocks
Authorization: Bearer or_test_…
Idempotency-Key: 3f1c9a52-7d0e-4b8f-9a61-0c2d5e8b7f14
Content-Type: application/json

{
  "name": "Monthly renewal",
  "frozenTime": "2026-10-20T09:00:00.000Z"
}
```

Response (`201`):

```json
{
  "id": "clk_01jacq4m3xf0v8w9zq2y7k5n6h",
  "object": "test_clock",
  "livemode": false,
  "brandId": "brd_01jacq4m3xf0v8w9zq2y7k5n6b",
  "name": "Monthly renewal",
  "frozenTime": "2026-10-20T09:00:00.000Z",
  "status": "ready",
  "advance": null,
  "version": 1,
  "createdAt": "2026-10-20T09:00:00.000Z",
  "updatedAt": "2026-10-20T09:00:00.000Z"
}
```

## Errors

| Code                                                                                     | HTTP status | When                                                                             | What to do                                                                                                                           |
| ---------------------------------------------------------------------------------------- | ----------- | -------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------ |
| [`validation_failed`](https://ownrecord.io/docs/reference/errors.md#validation_failed)   | 400         | The name is empty or too long, or `frozenTime` is out of range.                  | Fix the fields listed in `details.issues` and send the request again.                                                                |
| [`mode_not_supported`](https://ownrecord.io/docs/reference/errors.md#mode_not_supported) | 400         | The request is in live mode: test clocks exist in test mode only.                | Use the mode the operation supports (`details.supported_mode`): test-only operations such as test clocks need test-mode credentials. |
| [`permission_denied`](https://ownrecord.io/docs/reference/errors.md#permission_denied)   | 403         | The credentials can't manage this brand's subscriptions (`subscriptions:write`). | Ask an organization owner or admin for a role or scope that allows this action.                                                      |

It can also return these [common errors](https://ownrecord.io/docs/reference.md#common-errors): [`api_version_unsupported`](https://ownrecord.io/docs/reference/errors.md#api_version_unsupported), [`invalid_json`](https://ownrecord.io/docs/reference/errors.md#invalid_json), [`unsupported_media_type`](https://ownrecord.io/docs/reference/errors.md#unsupported_media_type), [`authentication_required`](https://ownrecord.io/docs/reference/errors.md#authentication_required), [`api_key_invalid`](https://ownrecord.io/docs/reference/errors.md#api_key_invalid), [`scope_required`](https://ownrecord.io/docs/reference/errors.md#scope_required), [`resource_not_found`](https://ownrecord.io/docs/reference/errors.md#resource_not_found), [`idempotency_key_required`](https://ownrecord.io/docs/reference/errors.md#idempotency_key_required), [`idempotency_key_reused`](https://ownrecord.io/docs/reference/errors.md#idempotency_key_reused), [`idempotency_in_progress`](https://ownrecord.io/docs/reference/errors.md#idempotency_in_progress), [`approval_required`](https://ownrecord.io/docs/reference/errors.md#approval_required), [`approval_rejected`](https://ownrecord.io/docs/reference/errors.md#approval_rejected), [`approval_expired`](https://ownrecord.io/docs/reference/errors.md#approval_expired), [`stale_approval`](https://ownrecord.io/docs/reference/errors.md#stale_approval), [`approval_policy_denied`](https://ownrecord.io/docs/reference/errors.md#approval_policy_denied), [`rate_limited`](https://ownrecord.io/docs/reference/errors.md#rate_limited), [`internal_error`](https://ownrecord.io/docs/reference/errors.md#internal_error).