> ## Documentation Index
> Fetch the complete documentation index at: https://docs.praxa.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Build event-driven automation

> Drive application workflows from Praxa SSE events and signed webhooks without duplicating effects.

Use SSE when a connected client needs low-latency progress. Use webhooks when
your backend needs durable asynchronous delivery. Many products use both.

```mermaid theme={null}
flowchart LR
  Run["Praxa run"] --> SSE["SSE progress"]
  Run --> Hook["Signed webhook"]
  SSE --> UI["Live user interface"]
  Hook --> Inbox["Durable webhook inbox"]
  Inbox --> Dedupe["Deduplicate by event ID"]
  Dedupe --> Workflow["Application workflow"]
```

## Example applications

* Update a progress UI while a mission runs.
* Start a downstream job only after a terminal event.
* Route an approval-needed event to an internal review queue.
* Reconcile a delivery after a network timeout without repeating the effect.
* Populate a warehouse from immutable event IDs and ordered sequences.

## Delivery rules

1. Verify a webhook over the exact raw body before parsing JSON.
2. Reject stale timestamps and invalid signatures.
3. Persist the event before returning 2xx.
4. Deduplicate by immutable event ID.
5. Process run events by sequence rather than arrival order.
6. Resume SSE with the last event ID.
7. Treat EOF before terminal as incomplete.

<CardGroup cols={2}>
  <Card title="Signed webhook tutorial" icon="webhook" href="/tutorials/webhooks">
    Implement verification, persistence, replay, and cleanup.
  </Card>

  <Card title="Event troubleshooting" icon="stethoscope" href="/troubleshooting/events-and-webhooks">
    Diagnose signatures, ordering, duplicate delivery, and stream gaps.
  </Card>
</CardGroup>