=== variant A: no CLAUDE.md ===
   FAIL  Add a function clamp(x, lo, hi) that limits x to the range [
   FAIL  Add a function is_even(n) to src/utils.py.
=== variant B: CLAUDE.md with the type-hint rule ===
   PASS  Add a function clamp(x, lo, hi) that limits x to the range [
   PASS  Add a function is_even(n) to src/utils.py.

score without rule: 0%   score with rule: 100%   -> ship the rule
