I think focusing on algorithms (if that's what you're suggesting) would be tunnel vision, and as a result the output of such a system will be much more weakly correlated with productivity than it should be.
Beyond code literacy, the most valuable skills for a 99% of programming roles are empathy and diligence. Unless you're working on the kind of programming that's arguably pure mathematics, algorithms are just not important.
There are plenty of ways to test diligence; empathy is a little harder to test directly but there are reasonable proxies.
Disclaimer: I'm working on a product for applicant filtering (generic rather than coder-specific) https://www.beapplied.com/
Beyond code literacy, the most valuable skills for a 99% of programming roles are empathy and diligence. Unless you're working on the kind of programming that's arguably pure mathematics, algorithms are just not important.
There are plenty of ways to test diligence; empathy is a little harder to test directly but there are reasonable proxies.
Disclaimer: I'm working on a product for applicant filtering (generic rather than coder-specific) https://www.beapplied.com/