It's hard to tell. Other similar options in other commands can mean things like "exit with status 0 even if errors are detected". Without installing pyrefly, I'm not sure what that flag's supposed to do. It's not documented on their site.

It adds a comment to suppress the error above each line in your codebase that causes an error, but it reports the errors before doing that, so you can only see the result after you re-run `pyrefly check`.

Oh! That's nifty. It leaves you with a baseline so you can stop making new mistakes, and gives you something to grep for when you want to fix existing ones.