# Streaming formats and reconnects

Event schemas, heartbeats, and reconnect logic for SSE and WebSocket.

- Date: Aug 28, 2025
- Reading time: 12 min
- Level: Intermediate
- Tags: Streaming, Responses, Realtime

## Takeaways
- Document event schemas with versioning.
- Use heartbeats to detect drops quickly.
- Resume sessions with replay tokens.

## Define event schemas

Publish a versioned event schema and enforce it on both client and server.

## Heartbeat and timeout

Send heartbeat events on a fixed interval to detect disconnects.

## Reconnect strategy

Use session IDs and replay tokens to resume streams without duplication.