generated: '2026-07-19'
method: searched
source: https://lkcloud-api.readme.io/docs/lk-cloud-overview
docs: https://lkcloud-api.readme.io/docs
authentication:
  style: OAuth 2.0 client_credentials Bearer token + non-secret SiteServiceKey routing header
  ref: authentication/ellkay-authentication.yml
transport:
  interop_style: JSON over HTTPS; Interop operations are invoked as POST requests
  fhir_style: FHIR R4 RESTful (read/search/create/update/delete) over HTTPS
  content_type: application/json
pagination:
  style: token / continuation
  pattern: >-
    Long/searched result sets use a Begin<Op> call that returns a next token, then
    repeated Next<Op> calls that carry the token until exhausted
  examples:
  - BeginSearchAppointments -> NextSearchAppointments
  response_field: token
idempotency:
  supported: false
  note: No idempotency-key contract is documented for the LKCloud or FHIR APIs.
request_tracing:
  field: Handle
  location: error response body
  format: GUID
  note: >-
    Every Interop error carries a Handle GUID that uniquely identifies the request within
    ELLKAY infrastructure; supply it when opening a support ticket.
error_envelope:
  interop:
    fields: [Detail, ErrorCode, Handle, Message, RecoverySteps, Type]
    ref: errors/ellkay-error-codes.yml
  fhir:
    resource: OperationOutcome
    note: >-
      FHIR errors are returned as an OperationOutcome resource; the API may return an
      OperationOutcome with issues even when the HTTP status is 200 OK, so clients must
      inspect response content.
rate_limiting:
  model: concurrency
  limit: 5 concurrent requests per SiteService Key
  recommendation: start at concurrency of 1 per data source; raise with ELLKAY technical contact
  external_signal: ExternalApiRateLimitReached error code surfaces downstream data-source limits
  ref: rate-limits/ellkay-rate-limits.yml
versioning:
  scheme: release-numbered (server-side API + FHIR module versioned separately)
  current_interop: 6.23.0
  breaking_change_policy: ELLKAY does not make breaking changes to the LKCloud APIs
  release_channel: new functionality deploys to Staging first with a release announcement
  ref: lifecycle/ellkay-lifecycle.yml
environments:
  staging: https://services.lkstaging.com
  production: https://services.lkcloud.com
  fhir_staging: https://fhir.lkstaging.com/R4
  fhir_production: https://fhir.lkcloud.com/R4
  ref: sandbox/ellkay-sandbox.yml