Data API

Send your orders, customers, product variants and refunds to Eyk over HTTPS, one object or a batch per request. Eyk stores every request and processes it in the night run.

Before you start

You need:

The Custom data page, read once.
The Custom Data API source added in Eyk under Sources.
An API key, created on the Configure tab of that source with Create API key. The key is shown once.
Your organization id, the UUID after /org/ in the URL of your Eyk environment.

Endpoints

Object	Endpoint	Key field
Product variant	`POST https://data-api.eykdata.com/v1/product_variants`	`id`
Customer	`POST https://data-api.eykdata.com/v1/customers`	`id`
Order	`POST https://data-api.eykdata.com/v1/orders`	`id`
Refund	`POST https://data-api.eykdata.com/v1/refunds`	`id`
Order update	`POST https://data-api.eykdata.com/v1/order_updates`	`order_id`
Product variant update	`POST https://data-api.eykdata.com/v1/product_variant_updates`	`id`

Every request carries the header X-API-Key and a JSON body: one object, or an array of up to 100 objects. Every object carries your organization_id. Timestamps are ISO 8601 with a timezone offset, for example 2026-03-14T10:15:00Z. Every field, with its type and meaning, is in the Data API reference.

Validate a first object

Send one product variant with debug=true. Eyk validates the object and your key and stores nothing. A 200 means the object is accepted.

curl -X POST 'https://data-api.eykdata.com/v1/product_variants?debug=true' \
  -H 'X-API-Key: YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "organization_id": "5f6a0c1e-2b3d-4e5f-8a9b-0c1d2e3f4a5b",
    "id": "VASE-BLU",
    "sku": "VB-001",
    "name": "Blue",
    "parent_id": "VASE",
    "parent_name": "Ceramic vase",
    "fallback_unit_cost": 8.50,
    "category_path": ["Home", "Vases"],
    "created_at": "2025-06-01T08:00:00Z",
    "updated_at": "2026-02-20T12:00:00Z"
  }'

Send variants and customers

Repeat without debug=true for every variant your order lines refer to, in batches of up to 100. Then send your customers to /v1/customers. email is required on a customer.

Send orders

Refer to the customer and the variants by id. Every amount excludes tax.

curl -X POST 'https://data-api.eykdata.com/v1/orders' \
  -H 'X-API-Key: YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "organization_id": "5f6a0c1e-2b3d-4e5f-8a9b-0c1d2e3f4a5b",
    "id": "NV-10432",
    "order_number": "#1043",
    "payment_status": "paid",
    "store_view_id": "nl",
    "store_view_name": "Noor & Vos NL",
    "sales_channel": "web",
    "created_at": "2026-03-14T10:15:00Z",
    "updated_at": "2026-03-14T10:15:00Z",
    "currency": "EUR",
    "subtotal": 90.00,
    "discounts": 10.00,
    "discount_codes": ["SPRING10"],
    "shipping": 5.00,
    "shipping_tax": 1.05,
    "taxes": 17.85,
    "customer": "CUST-8842",
    "shipping_address": { "country": "NL" },
    "items": [
      { "id": "NV-10432-1", "quantity": 2, "unit_price": 20.00, "taxes": 8.40, "product_variant": "VASE-BLU" },
      { "id": "NV-10432-2", "quantity": 1, "unit_price": 50.00, "discounts": 10.00, "taxes": 8.40, "product_variant": "TRAY-OAK" }
    ]
  }'

customer and product_variant also take the full object instead of the id. Then you can skip the separate customer and variant requests.

Send refunds

Send each refund to /v1/refunds with the order_id of the refunded order, the amount refunded for goods, and the refunded lines in items when you have them.

Send changes as they happen

Send a record again, in full, with a later updated_at whenever it changes. Per id the latest updated_at wins.

Send cost corrections

Optional. When a second system, such as an ERP, knows the real shipping cost or cost of goods, send an order update. Only the fields you name change. Per field, the update with the highest priority wins, then the latest occurred_at.

curl -X POST 'https://data-api.eykdata.com/v1/order_updates' \
  -H 'X-API-Key: YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
    "organization_id": "5f6a0c1e-2b3d-4e5f-8a9b-0c1d2e3f4a5b",
    "order_id": "NV-10432",
    "occurred_at": "2026-03-16T07:00:00Z",
    "source_system": "erp",
    "priority": 10,
    "shipping_cost": 4.35,
    "items": [{ "id": "NV-10432-2", "unit_cost": 21.00 }]
  }'

A field that was removed from the API is accepted and ignored, and the response carries a Warning header that names it.

Check it worked

Open the Custom Data API source in Eyk under Sources. The Monitor tab lists orders, refunds, product variants and customers received per day. Data appears in reports the morning after Eyk’s night run.

Troubleshooting

422 with a message about the timestamp

A timestamp has no timezone offset. Send 2026-03-14T10:15:00Z or 2026-03-14T12:15:00+02:00.

403 Forbidden

The API key does not belong to this organization_id. Check the id after /org/ in your Eyk URL, and the scope chosen when the key was created.

422 batch size exceeds maximum

The array holds more than 100 objects. Split it.

422 duplicate item IDs

Two lines in one order share an id. Line ids must be unique within the order.

200 but the order is missing in reports

Reports update once a night. If the order is still missing the next morning, check the Monitor tab for the day you sent it. Then check that its variant_id and customer_id values match records you sent.

Server-side tracking

Destinations

Agentic

How-to guides

Before you start

Endpoints

Check it worked

Troubleshooting

​Before you start

​Endpoints

​Check it worked

​Troubleshooting

Before you start

Endpoints

Check it worked

Troubleshooting