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fix heartbeat jitter inconsistency #8027

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fix heartbeat jitter inconsistency #8027

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2 changes: 1 addition & 1 deletion docs/events/gateway.mdx
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Expand Up @@ -145,7 +145,7 @@ Upon receiving the Hello event, your app should wait `heartbeat_interval * jitte
When sending a heartbeat, your app will need to include the last sequence number your app received in the `d` field. The sequence number is sent to your app in the [event payload](/docs/events/gateway-events#payload-structure) in the `s` field. If your app hasn't received any events yet, you can just pass `null` in the `d` field.

:::info
In the first heartbeat, `jitter` is an offset value between 0 and `heartbeat_interval` that is meant to prevent too many clients (both desktop and apps) from reconnecting their sessions at the exact same time (which could cause an influx of traffic).
In the first heartbeat, `jitter` is an offset value between 0 and 1 that is meant to prevent too many clients (both desktop and apps) from reconnecting their sessions at the exact same time (which could cause an influx of traffic).
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@Qjuh Qjuh Dec 11, 2025 •
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But that isn't an offset then. The offset value is heartbeat_interval * jitter.

:::

You *can* send heartbeats before the `heartbeat_interval` elapses, but you should avoid doing so unless necessary. There is already tolerance in the `heartbeat_interval` that will cover network latency, so you don't need to account for it in your implementation.
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