Like this: https://docs.gitlab.com/ee/user/application_security/coverag...

It won't tell you whether the software works correctly, it will just tell you if it raises an exception or crashes.

Put a fuzzer on Chrome for example, you won't catch most of the issues it has, though Chrome actually has tons of bugs and issues, but you may find security issues if you devote a big enough budget to run your fuzzer long time enough to cover all the branches.

So it's good in the case where you use "exceptions as tests", where any minor out-of-scope behavior raises an exception and all the cases are pre-planned (a bit like you baked-in runtime checks, and the fuzzer explores them)