> ## Documentation Index > Fetch the complete documentation index at: https://docs.fastcac.com/llms.txt > Use this file to discover all available pages before exploring further. # Change a test monitor's business > Test keys only: as if CAC's register now lists this status or name. Sends the same events a real change does. ## OpenAPI ````yaml /openapi.json post /test_helpers/businesses/monitors/{monitor_id}/changes openapi: 3.1.0 info: title: FastCAC API description: Register Nigerian businesses with CAC from your own product. version: '2026-11-01' servers: - url: https://api.fastcac.com/v1 security: - apiKey: [] tags: - name: Account description: Check your key and see your organization. - name: Names description: >- Check a business name against CAC's rules and registry, and the categories it takes, before registering it. - name: Registrations description: Register a Business Name with CAC, from draft to certificate. - name: Lookup description: >- Search CAC's register for free, and look up a business's full record with its officers. - name: Verification description: >- Check that a business your applicant names is real, active and run by the people they say. - name: Monitoring description: >- Watch businesses on CAC's register and get an event when one goes inactive or changes name. - name: Identities description: >- Look up a proprietor's NIN with NIMC, to prefill a registration and use their photo. - name: Balance description: >- Your prepaid wallet: what's available, its transactions and your funding account. - name: Test helpers description: >- Test keys only: move a registration on without waiting, or simulate a deposit. - name: Webhooks description: Endpoints that receive events, and the events sent to them. - name: Webhook events description: What FastCAC POSTs to your webhook endpoints. paths: /test_helpers/businesses/monitors/{monitor_id}/changes: post: tags: - Test helpers summary: Change a test monitor's business description: >- Test keys only: as if CAC's register now lists this status or name. Sends the same events a real change does. operationId: >- change_test_monitor_test_helpers_businesses_monitors__monitor_id__changes_post parameters: - name: monitor_id in: path required: true schema: type: string title: Monitor Id requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/MonitorChangeIn' example: status: INACTIVE responses: '200': description: Successful Response content: application/json: schema: $ref: '#/components/schemas/V1BusinessMonitor' examples: Example: value: object: business_monitor id: mon_5Rfxqm9UQ4xlFxXoJeFCaT number: '7654321' type: RC type_label: Company name: ADA FOODS LIMITED status: INACTIVE active: false external_id: merchant-4471 state: active paid_through: '2026-11-27T15:16:04Z' last_checked_at: null last_changed_at: '2026-10-28T15:16:05Z' amount_charged: null created_at: '2026-10-28T15:16:04Z' '400': description: The request is invalid; `param` names the field. content: application/json: schema: $ref: '#/components/schemas/Error' '401': description: The API key is missing, malformed, revoked or expired. content: application/json: schema: $ref: '#/components/schemas/Error' examples: Example: value: error: type: authentication_error code: api_key_missing message: 'Send your API key as `Authorization: Bearer `.' param: null request_id: req_8r9FEwNmLuxQORZX5Qhvkd0q '403': description: >- The key can't do this (for example, a test helper called with a live key). content: application/json: schema: $ref: '#/components/schemas/Error' examples: Example: value: error: type: permission_error code: test_mode_only message: The test helper only works with a test key. param: null request_id: req_gX65JwIgM2XO4SGn00mDcVUk '404': description: No such object for this key's organization and mode. content: application/json: schema: $ref: '#/components/schemas/Error' examples: Example: value: error: type: not_found_error code: resource_missing message: 'No such registration: reg_0000000000000000000000.' param: id request_id: req_PLJYvLLT2WjhIywrPjlhgIGv '409': description: >- The object's state doesn't allow this, or the Idempotency-Key was reused. content: application/json: schema: $ref: '#/components/schemas/Error' '429': description: Too many requests; wait for `Retry-After` seconds. content: application/json: schema: $ref: '#/components/schemas/Error' components: schemas: MonitorChangeIn: properties: status: anyOf: - type: string - type: 'null' title: Status description: The status CAC now lists, such as INACTIVE. name: anyOf: - type: string - type: 'null' title: Name description: The name CAC now lists. type: object title: MonitorChangeIn V1BusinessMonitor: properties: object: type: string const: business_monitor title: Object default: business_monitor id: type: string title: Id description: mon_… number: type: string title: Number type: type: string enum: - BN - RC - IT - LP - LLP title: Type type_label: type: string title: Type Label name: type: string title: Name description: The registered name at the last check. status: type: string title: Status description: >- CAC's status at the last check: ACTIVE, INACTIVE, STRUCK OFF and so on. active: type: boolean title: Active description: True when `status` is ACTIVE. external_id: anyOf: - type: string - type: 'null' title: External Id state: type: string enum: - active - paused - deleted title: State description: >- paused: a 30-day renewal couldn't be charged; it resumes once your wallet can pay. deleted: you stopped it. paid_through: type: string title: Paid Through description: When the current 30 days end; it renews then. last_checked_at: anyOf: - type: string - type: 'null' title: Last Checked At description: The last time CAC's register was read for it. last_changed_at: anyOf: - type: string - type: 'null' title: Last Changed At description: The last time its name or status changed. amount_charged: anyOf: - type: string - type: 'null' title: Amount Charged description: 'On create only: what the first 30 days cost.' created_at: anyOf: - type: string - type: 'null' title: Created At type: object required: - id - number - type - type_label - name - status - active - external_id - state - paid_through - last_checked_at - last_changed_at - created_at title: V1BusinessMonitor Error: properties: error: $ref: '#/components/schemas/ErrorDetail' required: - error title: V1Error type: object ErrorDetail: properties: type: type: string enum: - invalid_request_error - authentication_error - payment_error - permission_error - not_found_error - idempotency_error - rate_limit_error - api_error title: Type code: type: string title: Code description: Stable and machine-readable, e.g. registration_incomplete. message: type: string title: Message description: For a developer to read; may change. param: anyOf: - type: string - type: 'null' title: Param description: The parameter at fault, as a path like proprietors[0].nin. request_id: anyOf: - type: string - type: 'null' title: Request Id description: Also in the FastCAC-Request-Id header. Quote it to support. details: anyOf: - additionalProperties: true type: object - type: 'null' title: Details description: >- Only on some errors. A 402 insufficient_balance carries amount_due, balance, currency and funding_account (number, bank, name; null until it's active). type: object required: - type - code - message - param - request_id title: ErrorDetail securitySchemes: apiKey: type: http scheme: bearer description: 'Your secret API key: fc_test_… in test mode, fc_live_… in live mode.' ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.