generated: '2026-07-19'
method: searched
source: https://docs.finix.com/additional-resources/developers/authentication-and-api-basics
docs:
  authentication: https://docs.finix.com/additional-resources/developers/authentication-and-api-basics/api-keys
  idempotency: https://docs.finix.com/additional-resources/developers/authentication-and-api-basics/idempotent-request
  pagination: https://docs.finix.com/additional-resources/developers/authentication-and-api-basics/pagination
  versioning: https://docs.finix.com/additional-resources/developers/authentication-and-api-basics/versioning
  rate_limits: https://docs.finix.com/additional-resources/developers/authentication-and-api-basics/rate-limits
  errors: https://docs.finix.com/additional-resources/developers/implementation-and-testing/error-codes
authentication:
  style: HTTP Basic (RFC 7617)
  detail: API key ID + secret, Base64-encoded. See authentication/finix-authentication.yml.
idempotency:
  supported: true
  mechanism: request-body field
  field: idempotency_id
  scope: Supported on POST /transfers, POST /authorizations, and POST /transfers/{id}/reversals
  behavior: Ensures a create request is performed only once; protects against duplicate charges on retry.
  note: Webhook events also carry a system_generated_idempotency_id.
pagination:
  style: cursor
  params:
  - limit
  - after_cursor
  - before_cursor
  response_fields:
  - page.next_cursor
  - page.limit
  detail: Cursor-based pagination introduced in version 2022-02-01; use next_cursor with limit to page large lists.
versioning:
  style: date-header
  header: Finix-Version
  format: YYYY-MM-DD
  current: '2022-02-01'
  base_default: '2018-01-01'
  detail: Breaking changes ship as new dated versions; omitting the header defaults to 2018-01-01.
  see: lifecycle/finix-lifecycle.yml
error_envelope:
  style: HAL (application/hal+json)
  shape: '{ total, _embedded: { errors: [ { code, logref, message, _links } ] } }'
  transfer_fields:
  - failure_code
  - failure_message
  see: errors/finix-problem-types.yml
hypermedia:
  standard: HAL / HATEOAS
  detail: Responses embed related resources under _embedded and navigation under _links.
rate_limiting:
  detail: 100 requests/second reads and writes (Live); 429 TOO_MANY_REQUESTS on exceed.
  see: rate-limits/finix-rate-limits.yml
request_tracing:
  header: x-request-id
  detail: Requests may carry an x-request-id; the API returns a logref on errors for support correlation.