Oddly enough, just this morning RJBS was writing about rx aka Data::Rx, which I think tries to do what you want. And if it doesn't, then the blog post mentions a couple more options, JSON Schema and Kwalify that I don't know much about.

In reply to Re: "Schema" specifier for perl in memory structures by mirod
in thread "Schema" specifier for perl in memory structures by zerohero

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