If JFixture is unable to resolve a type for whatever reason the stack trace that gets printed is often massive and impossible to understand. There's a few things I can think of off the top of my head to help
Override toString on the xxxRequest classes (SeededRequest, etc) so the error message makes it clearer what the kernel was trying to resolve
Prune the stack trace, do developers really need to see everything? The TracingCustomisation adds useful information so the stack trace shouldn't really be needed
Related to this, it seems like the stack trace has lots of nesting when resolving fields in a test class. This looks really weird and shouldn't happen
If JFixture is unable to resolve a type for whatever reason the stack trace that gets printed is often massive and impossible to understand. There's a few things I can think of off the top of my head to help
toStringon the xxxRequest classes (SeededRequest, etc) so the error message makes it clearer what the kernel was trying to resolveTracingCustomisationadds useful information so the stack trace shouldn't really be needed