Debugging MQTT

Question: how to debug this and figure out what's wrong?

You can type mqtt in left side of the WebIDE to get details about the status.

Edit:

Sample output for not connected to the broker:

>mqtt
={
      svr: "test.mosquitto.org",
      prt: 1883, ka: 60, usr: undefined, pwd: undefined, cn: 0,
      ri: 2000, wt: undefined,
      wp: ""
 }
>