Issue 24, Oct 13, 2026

The Stateless Benchmark Trap

Senior AI Engineer interview at Microsoft, and the interviewer asks:

“Your coding agent resolves most isolated issues on your internal benchmark. But after it lands 20 consecutive tasks in the same repo, the team wants it turned off. What did your eval miss, and how would you measure it?”

Don’t say: “The benchmark needs harder issues and better test coverage.”

Why coding agents with high pass rates quietly destroy repos over 20 consecutive tasks and how stateful evaluation exposes the hidden degradation curve.

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