Workers seem a bit hopeless to me :( errors everywhere, logs nowhere

I have a working worker script.

I created a new subdomain and assigned the new script to it. All I am getting is a very informative HTTP 500 error.

If I am trying to use the quick edit HTTP GET feature, I am getting a 523 Origin Unreachable error for both despite one of them works. Playground equally doesn’t work, nor is it clear to me how is it even supposed to work to be fair.

There are no logs, verbose mode, debug headers , anything to help any of this out. How do you debug workers…?

BTW I figured out after I posted this that there was no Page Rule matching the new subdomain and that’s why but that’s neither here nor there – the question still comes up every time there’s an error : how do you debug any of this? I also see https://blog.cloudflare.com/cloudworker-a-local-cloudflare-worker-runner/ which helps not at all when the problem is with CF configuration. My worker primarily manipulates the request URL and it’s CF that produces that hence a local version at best finds some JS errors but none of the problems with the CF config.