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Rieck API

External references & metadata

Customers and invoices carry two integration fields (arriving on the API with the customer/invoice endpoints — the storage is live now so nothing needs backfilling):

  • externalReference — your id for the object (e.g. your order number). Unique per organisation and usable as a lookup key: GET /v1/invoices?externalReference=order-4711.
  • metadata — free key/value store returned on every response and webhook. Limits: max 50 keys, key ≤ 40 chars, value ≤ 500 chars, ≤ 8 KiB total. Never put personal data (PII) in metadata — use it for your own ids, flags and correlation values.

Updates are merge-safe: omitting the fields leaves them unchanged; sending null clears them. Editing an object in the Rieck portal never touches your integration fields.