Does Endless have an API, and what can a custom integration do with it?

Yes. Endless has a GraphQL API at https://api.endlesscommerce.com/graphql, and it is the same API the Endless app uses. To start, a company Admin or Owner creates a Custom App from Integrations and chooses the team role it needs. Existing Custom Sales, Custom Fulfillment, Operations, Custom Product, and Read Only Data integrations remain supported and can be converted while preserving their keys and history. The integration’s page shows an Access Token, which your developer sends in the X-EC-Access-Token header on every request, along with the Endpoint and the roles the integration has. To rotate the credentials, contact Endless support. Custom integrations need API access in your plan. The API reference is on docs.endlesscommerce.com.

The API documentation lists a separate sandbox endpoint. Ask Endless support to set up access to it.

A custom integration can create and manage purchase orders when its role allows it. An Operations Integration can create, update, cancel, and email purchase orders, register suppliers, and create and receive inbound shipments. Purchase orders also need Supply chain in your plan.

“Order with number … already exists” means the sales channel already has an order with that number, because order numbers must be unique within a sales channel. If you also send the order’s ID from your own system, Endless treats it as a duplicate only when the existing order has the same external ID or none. To change an existing order, use the update operations, such as updateOrderDetails and updateOrderItems, with the order’s Endless ID.

Endless can notify your systems through an automation with the Send Webhook action. It sends a signed HTTP POST to your URL when an order is created, or when a fulfillment order is created or becomes ready. After 20 consecutive failed deliveries, Endless pauses the webhook until you fix the endpoint and save the automation again. Automations must be in your plan. For other changes, such as shipments or cancellations, your developer or an AI coding tool can poll the orders query, which filters by status and shipment date. Contact Endless support to discuss other notifications.