generated: '2026-07-23'
method: searched
source: https://developer.aibgb.co.uk/apis
note: >-
  Cross-cutting request/response conventions for AIB Group (UK) Open Banking
  APIs. The public Open Data API follows the OBIE Open Data v2.2 conventions;
  the Read/Write family follows the OBIE Read/Write Data API v4.0 conventions
  (x-fapi headers, x-idempotency-key, standard error model). Captured from the
  developer portal and the OBIE standard, cross-referenced with the captured
  Open Data OpenAPI.
authentication:
  style: FAPI OAuth2/OIDC + mutual TLS (Read/Write); none (Open Data)
  ref: authentication/aib-group-uk-authentication.yml
idempotency:
  supported: true
  scope: Read/Write Payment Initiation (PIS) and Variable Recurring Payments (VRP)
  header: x-idempotency-key
  max_length: 40
  retention: >-
    OBIE requires idempotent handling of payment set-up/submission requests so a
    retried POST with the same x-idempotency-key and identical payload does not
    create a duplicate payment; a reused key with a different payload is rejected.
  standard: OBIE Read/Write Data API 4.0
fapi_headers:
  - name: x-fapi-auth-date
    description: Time the customer last logged in (RFC 7231 date).
  - name: x-fapi-customer-ip-address
    description: Customer IP address when the request is customer-present.
  - name: x-fapi-interaction-id
    description: RFC 4122 UUID echoed back for end-to-end request tracing.
  - name: x-jws-signature
    description: JWS detached signature over the payload for message integrity (payments).
request_tracing:
  header: x-fapi-interaction-id
  description: Client-supplied UUID echoed in the response for correlation.
pagination:
  style: link-based
  description: >-
    Read/Write list resources return a Links object (Self/First/Prev/Next/Last)
    and a Meta object with TotalPages; page size is bank-controlled. The Open
    Data API returns full collections with a Meta block (LastUpdated,
    TotalResults, Agreement, Licence, TermsOfUse).
conditional_requests:
  supported: true
  request_headers: [If-Modified-Since, If-None-Match]
  response_headers: [Etag, Cache-Control, Last-Modified]
  note: Open Data API supports ETag / If-None-Match conditional GETs.
versioning:
  style: uri-path
  examples: ['open-banking/v2.2 (Open Data)', 'v4.0 (Read/Write)', 'v3.2 (DCR)']
  ref: lifecycle/aib-group-uk-lifecycle.yml
error_envelope:
  shape: OBIE error model
  fields: ['Code', 'Id', 'Message', 'Errors[].ErrorCode', 'Errors[].Message', 'Errors[].Path', 'Errors[].Url']
  content_type_open_data: application/prs.openbanking.opendata.v2.2+json
  ref: errors/aib-group-uk-problem-types.yml
rate_limit_signaling:
  status: 429
  description: >-
    Open Data API returns HTTP 429 ("You have requested this resource too often.
    Slow down.") when the caller exceeds the polling rate. Read/Write APIs apply
    OBIE polling/rate constraints (e.g. event polling cadence).
security_headers:
  observed: [Strict-Transport-Security, X-Frame-Options, X-Content-Type-Options, Cache-Control]
  source: openapi/aib-group-uk-open-data-openapi.json