> ## Documentation Index > Fetch the complete documentation index at: https://docs.zapyd.com/llms.txt > Use this file to discover all available pages before exploring further. # Fetch Customer > Returns a customer's profile and status. Add the Zapyd "Fetch Customer" call (`GET /cms/api/v1/customer/{customer_id}`) to my backend. Returns a customer's profile and status. * Sandbox: `GET https://sandbox.zapyd.com/cms/api/v1/customer/{customer_id}` * Production: `GET https://api.zapyd.com/cms/api/v1/customer/{customer_id}` Path parameters: * `customer_id` (string, uuid, required): The unique identifier of the customer. Success: HTTP 200, `{status: true, message, data}`. `data`: `id`, `status`, `full_name`, `email`, `phone`, `country`, `client_reference_id`, `type`, `failure_reason`, `document_type`. Errors (`{status: false, message, err_code, errors}`): * 400 `Customer not found or access denied`: Customer not found; Customer does not belong to the organization * 500 `Internal Server Error` Every endpoint can also return 401 `AUTH_*` (signature, timestamp or key: fix, don't retry), and 429 or 5xx (retry with backoff). Rules: * Returns `status` (`UNVERIFIED`, `PROCESSING`, `VERIFIED`, `FAILED`) and `failure_reason`. Orders need `VERIFIED`. * Prefer webhooks. If you must poll, poll at most once a minute. The `CUSTOMER` webhook reports every KYC result. Signing (every request): * Headers: `X-API-KEY`, `X-TIMESTAMP` (Unix seconds, within 300 s of server time; generate per request) and `X-SIGNATURE`. * `X-SIGNATURE` = Base64(HMAC-SHA256(key = API secret, message = apiKey + "|" + timestamp + "|" + canonicalBody)). Base64 of the raw digest, not hex. * canonicalBody: the JSON body with keys sorted at every nesting level, no whitespace (separators `,` and `:`), and every non-ASCII character escaped as lowercase `\uXXXX` (Python `json.dumps(body, sort_keys=True, separators=(",", ":"))`). Requests with no body (GET, DELETE) sign `{}`. Query parameters are not signed. * Send the exact canonicalBody string you signed as the request body, with `Content-Type: application/json`. * Test vector: key `3f1b2c4d-5e6f-4a7b-8c9d-0e1f2a3b4c5d`, secret `test-secret-do-not-use`, timestamp `1735689600`. Signing `{}` gives `6sCtVSRQjU9+2/af8gdwUAvY1l6Ii6ENcbRfanPkhY0=`. Body `{"customer_id":"78c99d71-f28f-47a9-8302-93b286efbe0e","amount":100.5,"currency":"INR","meta":{"note":"Café","b":2,"a":1}}` gives `l+DvQrzlKbsOSxSYOdWoWHEehcFRZfDJPKlLDkm2cSI=`. Deliver: 1. A typed `fetchCustomer` function in this codebase's language and HTTP client. Reuse an existing Zapyd client and signer, or write one small shared client. 2. Config from `ZAPYD_API_KEY`, `ZAPYD_API_SECRET` and `ZAPYD_BASE_URL`. The secret stays on the server, never in a browser or app. 3. Return `data`. When `status` is false, throw an error with the HTTP status, `err_code`, `message` and `errors`. Don't show raw errors to end users. 4. Retry only 429 and 5xx: exponential backoff from 1 s, capped at 30 s, at most 5 attempts. 5. Amounts as strings. Types for every field above. 6. Tests: the signer against the test vector, and this call against sandbox. Reference: `https://docs.zapyd.com/api-reference-exchange/endpoint/customer/{customer_id}.md` | API Status Code | Response | Reason | | - | - | - | | 400 | Customer not found or access denied | Customer not found | | 400 | Customer not found or access denied | Customer does not belong to the organization | | 500 | Internal Server Error. | Internal Server Error | ## OpenAPI ````yaml GET /customer/{customer_id} openapi: 3.1.0 info: title: Zapyd API description: API for Zapyd - Customer, Payout, and Webhook services license: name: MIT version: 1.0.0 servers: - url: https://sandbox.zapyd.com/pos/api/v1 description: Payout API Base URL variables: base_url: default: https://sandbox.zapyd.com - url: https://sandbox.zapyd.com/cms/api/v1 description: Customer API Base URL variables: base_url: default: https://sandbox.zapyd.com security: - ApiKeyAuth: [] TimestampAuth: [] SignatureAuth: [] tags: - name: Customer description: Customer related operations x-displayName: Customer x-traitTag: true - name: Payout description: Payout related operations - name: Webhooks description: Webhook related operations - name: Widget description: Hosted buy/sell widget session initialization paths: /customer/{customer_id}: get: tags: - Customer description: Fetch details of a customer by ID parameters: - name: customer_id in: path required: true description: The unique identifier of the customer schema: type: string format: uuid example: 550e8400-e29b-41d4-a716-446655440000 responses: '200': description: Customer details fetched successfully content: application/json: schema: type: object properties: status: type: boolean example: true message: type: string example: Success data: type: object properties: id: type: string format: uuid example: 550e8400-e29b-41d4-a716-446655440000 status: type: string example: VERIFIED full_name: type: string example: John Doe email: type: string example: john.doe@example.com phone: type: string example: '+1234567890' country: type: string example: USA client_reference_id: type: string example: cust_12345 type: type: string example: INDIVIDUAL failure_reason: type: 'null' example: null document_type: type: string example: AADHAAR '400': description: Bad Request content: application/json: schema: type: object properties: status: type: boolean example: false message: type: string example: Bad Request err_code: type: string example: INPUT_MALFORMED errors: type: object additionalProperties: type: array items: type: string example: customer_id: - customer_id is required data: type: 'null' '500': description: Internal Server Error content: application/json: schema: type: object properties: status: type: boolean example: false message: type: string example: Internal Server Error data: type: 'null' err_code: type: string example: SYS_INTERNAL_ERROR errors: type: string example: Unexpected error occurred. Please try again later. servers: - url: https://sandbox.zapyd.com/cms/api/v1 description: Customer API Base URL components: securitySchemes: ApiKeyAuth: type: apiKey in: header name: X-API-KEY description: API Key for authentication TimestampAuth: type: apiKey in: header name: X-TIMESTAMP description: Current timestamp in seconds since epoch SignatureAuth: type: apiKey in: header name: X-SIGNATURE description: HMAC SHA256 signature of the request encoded in Base64 ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.