Courier to RudderStack
Configuration
Add a source that would essentially be the origin for events sent from Courier could just be a Node.js source). Once a source is added, copy over write key and data plane URL to Courier RudderStack integration page.
Event sourcing
Courier would start sending the events generated (like Message Sent for instance) to your RudderStack instance. This should show up on your RudderStack source page.