To prevent #[0] from flooding again, maybe checking the last message he send could be a "all sort of problems" solution.

#!bin/bash

hexpubkey="0000005f87f64341c212cc93d6c266c03ae752c02660e78a6da1424f7b05c470"

lastmessage="nostreq --authors \"$hexpubkey\" --limit 1 --kinds 1 | nostcat wss://relay.nostr.band | jq -r '.[2].content'"

eval $lastmessage