> For the complete documentation index, see [llms.txt](https://doc.duaer.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.duaer.com/build/sse-trigger.md).

# Start on Server-Sent Events with SSE Trigger

In Duaer, SSE Trigger starts the digital organization when Server-Sent Events arrive. URL is required. Event data must be JSON.
## Listen to an SSE URL

1. Search for SSE Trigger and place it at the start of the canvas.
2. Set URL to the SSE source, for example https://example.com/events.
3. Select Execute step, then push a test event from the source.
4. Publish so the trigger keeps listening.

Each message data field is parsed as JSON into an output item.

For one-shot HTTP callbacks, use [Receive a request with Webhook in Duaer](/build/webhook.md). To call APIs, see [Call an API with HTTP Request in Duaer](/build/http-request.md).
## Questions

### How is SSE Trigger different from Webhook in Duaer?

SSE Trigger connects out to a remote event stream. Webhook receives inbound HTTP requests to Duaer.

## Related

- [Receive a request with Webhook in Duaer](https://doc.duaer.com/build/webhook.md)
- [Reply to a caller with Respond to Webhook in Duaer](https://doc.duaer.com/build/respond-to-webhook.md)
- [Call an API with HTTP Request in Duaer](https://doc.duaer.com/build/http-request.md)