> ## Documentation Index > Fetch the complete documentation index at: https://commet.co/docs/llms.txt > Use this file to discover all available pages before exploring further. # Advance test clock > Starts a durable run that moves the test clock forward and processes every billing deadline due before the target time. Poll GET /test-clock for progress and terminal results. Sandbox only. Starts a durable run that moves the test clock forward and processes every billing deadline due before the target time. Poll GET /test-clock for progress and terminal results. Sandbox only. ## OpenAPI ````yaml /openapi/es/rest/2026-08-27.json post /test-clock openapi: 3.1.0 info: title: Commet API version: '2026-08-27' description: Billing and payments API for SaaS and AI products. servers: - url: https://commet.co/api/v1 security: - ApiKeyAuth: [] tags: - name: Test Clock description: >- Simulate the passage of time in sandbox to test billing flows. Mirrors Stripe test clocks: forward-only and sandbox-only. - name: Customers - name: Subscriptions - name: Plans - name: Markets description: >- Reusable country groups for market-specific prices and selectable price variants. - name: Offers - name: Promo Codes - name: Features - name: Usage - name: Seats - name: Quota - name: Add-ons - name: Portal - name: Credit Packs - name: Plan Groups - name: Invoices - name: Payments description: >- One-time payments with no subscription or plan. Charge a customer's saved payment method off-session, or create a payment link the customer opens to pay. Tax, invoice, and receipt are handled automatically. - name: Transactions - name: Webhooks - name: API Keys - name: Payouts description: >- Withdraw available balance to your bank and manage the payout account (verification + destination bank accounts). - name: Provisioning description: >- Take ownership of an organization an agent provisioned headlessly. The agent holds the API keys from the start; a human claims the account through a claim link. paths: /test-clock: post: tags: - Test Clock summary: Advance test clock description: >- Starts a durable run that moves the test clock forward and processes every billing deadline due before the target time. Poll GET /test-clock for progress and terminal results. Sandbox only. operationId: advance-test-clock parameters: - name: Idempotency-Key in: header required: false description: >- Unique key used to safely retry this write for 24 hours without applying it twice. schema: type: string minLength: 1 maxLength: 200 - name: Commet-Version in: header required: false description: >- API version used by this reference. Send this header to select this contract explicitly. schema: type: string default: '2026-08-27' example: '2026-08-27' requestBody: required: true content: application/json: schema: oneOf: - type: object properties: advanceDays: type: integer exclusiveMinimum: 0 maximum: 9007199254740991 required: - advanceDays additionalProperties: false - type: object properties: frozenTime: type: string format: date-time required: - frozenTime additionalProperties: false responses: '202': description: Success headers: X-Request-Id: $ref: '#/components/headers/RequestId' RateLimit-Limit: description: Maximum number of requests allowed in the current window. schema: type: string RateLimit-Remaining: description: Requests remaining in the current window. schema: type: string content: application/json: schema: $ref: '#/components/schemas/TestClockRun' example: id: run_1a2b3c4d status: pending startedAtTime: '2026-09-07T12:00:00.000Z' targetTime: '2026-10-07T12:00:00.000Z' estimatedDeadlineCount: 1 completedDeadlineCount: 0 failedDeadlineCount: 0 error: null items: [] object: test_clock_run livemode: false '400': description: Bad request headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: validation_error code: validation_error message: The request contains an invalid parameter. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/validation_error.md '401': description: Unauthorized headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: authentication_error code: unauthorized message: A valid API key is required. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/unauthorized.md '403': description: Forbidden headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: authentication_error code: forbidden message: You do not have permission to perform this operation. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/forbidden.md '409': description: Conflict headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: conflict_error code: idempotency_in_progress message: >- A request with this idempotency key is still being processed. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/idempotency_in_progress.md '429': description: Too many requests headers: X-Request-Id: $ref: '#/components/headers/RequestId' RateLimit-Limit: description: Maximum number of requests allowed in the current window. schema: type: string RateLimit-Remaining: description: Requests remaining in the current window. schema: type: string RateLimit-Reset: description: Seconds until the rate limit window resets. schema: type: string Retry-After: description: Seconds to wait before retrying the request. schema: type: string content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: rate_limit_error code: rate_limited message: >- Too many requests. Retry after the interval specified in the Retry-After header. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/rate_limited.md '500': description: Internal server error headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: internal_error code: internal_error message: An unexpected error occurred while processing the request. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/internal_error.md '503': description: Service unavailable headers: X-Request-Id: $ref: '#/components/headers/RequestId' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: type: internal_error code: idempotency_unavailable message: >- Idempotency storage is temporarily unavailable. Retry with the same idempotency key. doc_url: >- https://commet.co/docs/api-reference/2026-08-27/errors/idempotency_unavailable.md x-codeSamples: - lang: typescript label: TypeScript source: >- import { Commet } from "@commet/node"; const commet = new Commet({ apiKey: "ck_xxx" }); const testClockRun = await commet.testClock.advance({ advanceDays: 30 }); - lang: python label: Python source: |- from commet import Commet commet = Commet("ck_xxx") test_clock_run = commet.test_clock.advance(advance_days=30) - lang: go label: Go source: "client, err := commet.New(\"ck_xxx\")\nif err != nil {\n\tlog.Fatal(err)\n}\nctx := context.Background()\n\ntestClockRun, err := client.TestClock.Advance(ctx, &commet.AdvanceTestClockParams{\n\tAdvanceDays: func(value int) *int { return &value }(30),\n})\nif err != nil {\n\tlog.Fatal(err)\n}" - lang: java label: Java source: |- import co.commet.Commet; import co.commet.params.AdvanceTestClockParams; var commet = Commet.builder().apiKey("ck_xxx").build(); var testClockRun = commet.testClock().advance( AdvanceTestClockParams.builder().advanceDays(30L).build() ); - lang: php label: PHP source: |- use Commet\Commet; $commet = new Commet('ck_xxx'); $testClockRun = $commet->testClock->advance(advanceDays: 30); components: headers: RequestId: description: >- Server-generated identifier that correlates this response with Platform logs. schema: type: string format: uuid schemas: TestClockRun: type: object properties: id: type: string status: type: string enum: - pending - running - completed - failed startedAtTime: type: string format: date-time targetTime: type: string format: date-time estimatedDeadlineCount: type: integer minimum: -9007199254740991 maximum: 9007199254740991 completedDeadlineCount: type: integer minimum: -9007199254740991 maximum: 9007199254740991 failedDeadlineCount: type: integer minimum: -9007199254740991 maximum: 9007199254740991 error: anyOf: - type: string - type: 'null' items: type: array items: type: object properties: kind: type: string enum: - billing_cycle - dunning_retry status: type: string enum: - pending - processing - completed - failed dueAt: type: string format: date-time subscriptionId: type: string customerName: anyOf: - type: string - type: 'null' invoiceNumber: anyOf: - type: string - type: 'null' invoiceId: anyOf: - type: string - type: 'null' outcome: anyOf: - type: string - type: 'null' detail: anyOf: - type: string - type: 'null' error: anyOf: - type: string - type: 'null' required: - kind - status - dueAt - subscriptionId - customerName - invoiceNumber - invoiceId - outcome - detail - error additionalProperties: false object: type: string const: test_clock_run livemode: type: boolean required: - id - status - startedAtTime - targetTime - estimatedDeadlineCount - completedDeadlineCount - failedDeadlineCount - error - items - object - livemode additionalProperties: false ErrorResponse: type: object properties: error: type: object properties: type: type: string code: type: string message: type: string param: type: string details: {} doc_url: type: string required: - type - code - message - doc_url additionalProperties: false required: - error additionalProperties: false securitySchemes: ApiKeyAuth: type: apiKey in: header name: x-api-key ```` ## Related topics - [Testing](/docs/es/testing-sandbox.md) - [CLI](/docs/es/cli.md) - [Get test clock state](/docs/es/api-reference/test-clock/get-test-clock.md) - [Deprecated manual billing processing](/docs/es/api-reference/test-clock/process-test-clock-billing.md) - [Ejemplos](/docs/es/examples.md) This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.