Open API / Webhooks
Trigger mail sends and upload recipient data directly from your own systems using LettrLabs' API and webhooks.
By Adam and 1 other2 authors3 articles
- Setup Guide: Open API & WebhooksHow to generate an Open API key and set up inbound webhooks to trigger mail or attribution from your own systems.
- Inbound Webhook Reference (Payload & Field Guide)Technical reference for developers: request format, authentication, response codes, and field shapes for each webhook action type.
- Adding a duplicate recipient to an integration orderPOST /v1/integration-orders/{id}/recipients now returns HTTP 200 for an exact duplicate recipient. DUPLICATE_RECIPIENT left the 422 reason-code list.