Bash and Applescript to send iMessage

$ cat imessage.sh
#!/usr/bin/env bash

set -ex

message=$1

osascript <<EOF

    tell application "Messages"
        set myid to get id of first service
        set theBuddy to buddy "+1xxxxxxxxxx" of service id myid
        send "$message" to theBuddy
    end tell

EOF

exit 0

Usage: ./imessage.sh "enter message here"