Rubric
This scorer applies only to implementation-agent runs, including a later revision re-entry. It grades the final delivered test diff — the tests and cases that landed on the PR after self-review — not intermediate tests the agent wrote and then deleted, and not whether a human later asked to remove them (that event is unnecessary-tests-human-correction). The question is surplus in the artifact: redundant, tautological, or low-signal tests that would not fail on a real defect any other added or existing test misses.
This is a within-run ordinal so the across-run frequency is the sampled fail rate. samplingRate is 100. passingScore is 0.5, which means any surplus fails the run: mostly_surplus_tests (0.2) and some_surplus_tests (0.4) both fail, with the two ordinals keeping a material share of surplus distinguishable from a minority of low-signal cases. no_surplus_tests (1) is a clean pass. insufficient_evidence (0.5) is a pass at the threshold, not a clean pass: it keeps missing co