Do I need a key or account?
No. KrulHub has no key system. Paste the loadstring into your executor, accept the in-game consent popup, and the script runs - that's it.
Is it safe to run?
Every script shows a consent popup before anything executes, and public scripts are open source - you can read the exact code before running it. Nothing is hidden.
Can I see the source?
Yes, for any script the author has marked public. Read it, fork it, or self-host it - just keep the original author credit in the header.
The popup closed but nothing happened
Almost always an executor compatibility issue - your executor is missing an API the script needs. Use an executor that meets the sUNC standard.