It should display real error message

[natureisbestNFT]

eg it says
Broadcasting split tx
Error executing operation: Request failed with status code 500

Using wireshark or tshark shows the real error was {"result":null,"error":{"code":-26,"message":"64: tx-size"},"id":0}

For local node use interface 'lo', for remote node use appropriate interface, eg in linux bash as root:
tshark -i lo -f "port 22555" -c 200000
tail -f /var/tmp/wireshark_lo*.pcapng | grep -a error