generated: '2026-07-21'
method: searched
source: developer.veem.com docs (oauth, webhook-notifications, versioning) + openapi/veem-api-openapi.yml
docs:
  - https://developer.veem.com/docs/oauth
  - https://developer.veem.com/docs/webhook-notifications
  - https://developer.veem.com/docs/veem-errors
description: >-
  Cross-cutting request/response semantics of the Veem Public API, captured
  from the developer portal and derived from the harvested OpenAPI. Veem is a
  B2B global-payments API: OAuth2 bearer auth, URI-path versioning
  (/veem/v1.2/...), a mandatory per-request X-Request-Id UUID that doubles as
  duplicate-request protection, page-number pagination on list endpoints, and
  a flat code/message error envelope with numeric Veem error codes.
authentication:
  style: OAuth 2.0 bearer token (two-legged client_credentials or three-legged authorization_code)
  header: 'Authorization: Bearer <access_token>'
  artifact: authentication/veem-authentication.yml
idempotency:
  supported: true
  mechanism: request-id header
  header: X-Request-Id
  format: UUID
  required: true
  semantics: >-
    Every write request must carry a unique X-Request-Id (UUID). Reusing an
    X-Request-Id value returns 409 Conflict, preventing duplicate processing of
    the same request (duplicate-submission protection rather than a
    stored-response replay a la Stripe's Idempotency-Key). Payment webhook
    payloads echo the originating request as originalRequestId.
  docs: https://developer.veem.com/docs/webhook-notifications
versioning:
  scheme: uri-path
  current: v1.2
  pattern: /veem/{version}/... (some payment/wallet endpoints remain on v1.0)
  portal_versions: [v1.1, v1.2, v2.0]
  docs: https://developer.veem.com/docs/versioning
  artifact: lifecycle/veem-lifecycle.yml
pagination:
  style: page-number
  request_params: [pageNumber, pageSize]
  operations: [getContactsUsingGET_2, getCryptoWalletTransactions]
  source: openapi/veem-api-openapi.yml
request_tracing:
  header: X-Request-Id
  direction: request
  notes: Same header that provides duplicate protection; UUID format, unique per API request.
error_envelope:
  shape: '{code, error, message, timestamp} (ErrorResponse) / {code, message, logTag, timestamp, ...} (VeemErrorResponse)'
  code_style: numeric Veem error codes (e.g. 50001202 INVALID_EMAIL_ADDRESS)
  artifact: errors/veem-error-codes.yml
  derived_status_codes: [200, 201, 400, 401, 403, 404, 409, 500]
content_type: 'application/json (requests require Content-Type: application/json)'
rate_limits:
  documented: false
  notes: No public rate-limit reference or rate-limit response headers documented on the developer portal.
webhooks:
  artifact: asyncapi/veem-webhooks.yml
  signature_header: ACCESS-SIGNATURE (HMAC-SHA256 keyed with your clientId over the payload)
field_expansion:
  documented: false
metadata:
  documented: false