> ## 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. # Check a business name ## OpenAPI ````yaml /openapi.json post /name-checks 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: Name checks description: >- Check a business name against CAC's rules and registry before registering it. - name: Registrations description: Register a Business Name with CAC, from draft to certificate. - name: Test helpers description: 'Test keys only: move a registration on without waiting.' - 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: /name-checks: post: tags: - Name checks summary: Check a business name operationId: name_check_name_checks_post parameters: - name: simulate in: query required: false schema: anyOf: - type: string - type: 'null' description: >- Test keys only: force an outcome (available, requires_certificate, or a reason code such as name_exists). Ignored with a live key. title: Simulate description: >- Test keys only: force an outcome (available, requires_certificate, or a reason code such as name_exists). Ignored with a live key. requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/NameCheckIn' example: name: Ada Foods Ventures line_of_business: Educational Services And Consultancy responses: '200': description: Successful Response content: application/json: schema: $ref: '#/components/schemas/V1NameCheck' examples: Available: value: object: name_check name: ADA FOODS VENTURES line_of_business: Educational Services And Consultancy available: true requires_certificate: false reason: null similarity_score: 12.5 most_similar_name: null similar_names: [] suggested_names: [] Qualifier missing: value: object: name_check name: ADA FOODS line_of_business: Educational Services And Consultancy available: false requires_certificate: false reason: code: qualifier_missing message: >- A business name must end in a qualifier such as VENTURES, ENTERPRISES or CONCEPTS. accepted_qualifiers: - VENTURES - ENTERPRISES - HUB - CONCEPTS - FASHION - SERVICES - BEAUTY - BIZ words: null conflicting_name: null similarity_score: null most_similar_name: null similar_names: [] suggested_names: [] Name exists: value: object: name_check name: ADA FOODS VENTURES line_of_business: Educational Services And Consultancy available: false requires_certificate: false reason: code: name_exists message: >- A business with this name is already registered with CAC. accepted_qualifiers: null words: null conflicting_name: ADA FOODS VENTURES similarity_score: 100 most_similar_name: ADA FOODS VENTURES similar_names: - ADA FOODS VENTURES suggested_names: - ADA FOODS CONCEPTS - ADA FOODS HUB '400': description: The request is invalid; `param` names the field. content: application/json: schema: $ref: '#/components/schemas/Error' examples: Example: value: error: type: invalid_request_error code: parameter_invalid message: Pick what your business does from the list. param: line_of_business request_id: req_NkrrBEAzdQf6jFIJIK92ZAU7 '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_kdwpKsFMKS4VzLjqZJ0ntdrl '403': description: >- The key can't do this (for example, live registrations before they open). content: application/json: schema: $ref: '#/components/schemas/Error' examples: Example: value: error: type: permission_error code: live_mode_unavailable message: >- Live registrations aren't open yet. Use a test key (fc_test_…) for now. param: null request_id: req_oYVCIHqeYbgIA3lIzwG0PO5r '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_RlcFqswqrJZos4pnRMH3wa8d '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: NameCheckIn: properties: name: type: string maxLength: 100 title: Name line_of_business: type: string title: Line Of Business description: One of GET /v1/lines-of-business. type: object required: - name - line_of_business title: NameCheckIn V1NameCheck: properties: object: type: string const: name_check title: Object default: name_check name: type: string title: Name description: The name as CAC will record it (upper case, single spaces). line_of_business: type: string title: Line Of Business available: type: boolean title: Available requires_certificate: type: boolean title: Requires Certificate description: >- Available, but CAC will want a professional certificate (upload it as a supporting_document). reason: anyOf: - $ref: '#/components/schemas/V1NameCheckReason' - type: 'null' description: Why it isn't available; null when it is. similarity_score: anyOf: - type: number - type: 'null' title: Similarity Score description: How close (0-100) the nearest registered name is. most_similar_name: anyOf: - type: string - type: 'null' title: Most Similar Name similar_names: items: type: string type: array title: Similar Names suggested_names: items: type: string type: array title: Suggested Names description: Names to try instead. type: object required: - name - line_of_business - available - requires_certificate - reason - similarity_score - most_similar_name - similar_names - suggested_names title: V1NameCheck Error: properties: error: $ref: '#/components/schemas/ErrorDetail' required: - error title: V1Error type: object V1NameCheckReason: properties: code: type: string enum: - name_exists - name_too_similar - qualifier_missing - qualifier_not_last - multiple_qualifiers - single_word - restricted_word - restricted_line_of_business - offensive_language - religious_reference - special_characters - low_compliance - not_accepted title: Code message: type: string title: Message accepted_qualifiers: anyOf: - items: type: string type: array - type: 'null' title: Accepted Qualifiers description: With the qualifier codes. words: anyOf: - items: type: string type: array - type: 'null' title: Words description: 'With restricted_word: the words CAC doesn''t allow.' conflicting_name: anyOf: - type: string - type: 'null' title: Conflicting Name description: With name_exists and name_too_similar. type: object required: - code - message title: V1NameCheckReason ErrorDetail: properties: type: enum: - invalid_request_error - authentication_error - permission_error - idempotency_error - rate_limit_error - api_error title: Type type: string code: description: Stable and machine-readable, e.g. registration_incomplete. title: Code type: string message: description: For a developer to read; may change. title: Message type: string param: anyOf: - type: string - type: 'null' description: The parameter at fault, as a path like proprietors[0].nin. title: Param request_id: anyOf: - type: string - type: 'null' description: Also in the FastCAC-Request-Id header. Quote it to support. title: Request Id required: - type - code - message - param - request_id title: ErrorDetail type: object 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.