Close Codes

The WebSocket close codes the exchange sends, what each means, and how to recover.

A close code ends the whole connection. Errors scoped to one command or one subscription arrive as error frames instead, and each operation page lists the codes it can send. Codes in the 1000 range are the standard WebSocket close codes; codes in the 4000 range are specific to the exchange.

Code	Meaning
`1000`	Normal closure; reconnect only when another session is needed.
`1001`	Session lifetime or idle bound expired; reconnect and resubscribe.
`1002`	WebSocket protocol error; fix the client before reconnecting.
`1003`	Unsupported application data; send JSON text messages.
`1007`	Invalid UTF-8; fix the client before reconnecting.
`1008`	Repeated invalid or abusive input; back off and fix the client.
`1009`	Frame too large; send a smaller command.
`1011`	Unexpected server failure; reconnect with backoff and rebuild local state.
`1012`	Service restart, drain, or loss of a shared upstream source; reconnect with backoff and resubscribe. Events between the close and the new subscription are not replayed.
`1013`	Temporary service or admission failure; reconnect with backoff and rebuild local state.
`4001`	Authorization revoked; re-authenticate before reconnecting.
`4003`	Slow consumer or outbound memory bound; repair consumption, reconnect, and rebuild local state. This close frame is best effort, so an abnormal close is equivalent.

After any close, reconnect with backoff, authenticate again, resubscribe, and rebuild state. See Connecting.