How to check if the server is running?

Question

JavaScript

Good evening, there is a small script that describes the statefull server on node.js.
The essence is this : the server accepts 3 commands "open", "add", "process". They can only be listed in this order. The server responds to each command, and the correctness of the sequence is checked when each command is entered.
How can it be checked?
In the console or not in the console - it makes no difference.
You just need to get a response.
I tried, in console:

node file_name.js
curl -x -v open
open
-x open
...

Commands remain unanswered.