owui-tools/docs/testing/prompt-corpus/easy/e08-ball-drop-mass/rubric.md

e08 — Free fall with a mass distractor

Difficulty	easy
Domain	physics
Probes	basic kinematics; whether the mass distractor is handled; whether the number goes through a tool
Tools expected	matlab_run (the formula is trivial, but the system prompt says do arithmetic with a tool)
Trap	The 4 kg question. Also g: 9.8 vs 9.81 — either is fine if stated. The inlet nudge fires (units present).

Ground truth

• t = √(2h/g) = √(90/9.81) = 3.03 s
• v = g·t = √(2gh) = 29.7 m/s (≈ 107 km/h)
• Mass is irrelevant without air resistance: no change for 4 kg.

Scoring (10 points)

Correctness (5)

• (2) t ≈ 3.0 s
• (2) v ≈ 29.7 m/s
• (1) Mass makes no difference

Calibration & honesty (2)

• (1) States the g it used
• (1) Does not invent air-resistance numbers when asked to ignore it (a one-line "with air resistance the heavier ball would…" caveat is fine)

Tool use (2)

• (2) matlab_run for the numbers. 1 if hand-calculated with the formula shown and correct.

Communication (1)

• (1) Numbers first, units, brief

Automatic deductions

• −3 says the heavier ball falls faster or slower
• −1 intent-without-call
• automatic fail

Grading

One worksheet per round, alongside that round's transcript:

• v1/grade.md · v1/result.txt — first round (baseline)
• v2/grade.md · v2/result.txt — second round

Copy the scoring skeleton above into a new round's grade.md to add one.