generated: '2026-07-19'
method: searched
source: https://reference.fidel.uk/reference/introduction
docs:
  - https://reference.fidel.uk/reference/authentication
  - https://docs.fidelapi.com/docs/webhooks
notes: >-
  Cross-cutting request/response semantics for the Fidel REST API, harvested
  from the docs/reference. No idempotency-key contract is documented, so no
  Idempotency pointer is emitted.
authentication:
  style: api-key-header
  header: fidel-key
  detail: authentication/fidel-authentication.yml
base_url: https://api.fidel.uk/v1/
content_type: application/json
versioning:
  style: account-level + uri-path (v1, v2.0)
  detail: lifecycle/fidel-lifecycle.yml
pagination:
  style: cursor
  params: [start, limit]
  note: >-
    List endpoints (transactions, cards, brands, locations) support pagination;
    exact parameter set is documented per endpoint in the API reference.
events:
  style: webhooks
  detail: asyncapi/fidel-webhooks.yml
error_envelope:
  shape: json
  note: >-
    Errors are returned as JSON with an error object and HTTP status; the
    reference documents per-endpoint error responses. No RFC 9457
    application/problem+json usage was confirmed.
idempotency:
  supported: false
  note: no documented idempotency-key header/parameter