# discovery
coap-client -v9 -m get -A 40 coap://<esp-ip>/.well-known/core

# other resources
coap-client -v9 -m get coap://<esp-ip>/sys/uptime
coap-client -v9 -m get coap://<esp-ip>/net/rssi
coap-client -v9 -m get coap://<esp-ip>/led
coap-client -v9 -m put -e "on"  coap://<esp-ip>/led
coap-client -v9 -m put -e "off" coap://<esp-ip>/led
coap-client -v9 -m post -e "hello" coap://<esp-ip>/echo