Teacher bake-off — Model G (solution generator)

Data-driven teacher selection. 40 NuminaMath-CoT problems, one solution each, graded by boxed-answer equivalence (scripts/teacher_bakeoff.py).

scripts/teacher_bakeoff.py --models gpt-5.6-sol claude-opus-4-8 claude-sonnet-5 --n 40

model	keep-rate	median tok	p90 tok	% over 2048	sec/ex
claude-opus-4-8	57%	155	703	0%	6.7
gpt-5.6-sol	32%	103	324	0%	10.4
claude-sonnet-5	12%	224	691	0%	9.9

Winner: claude-opus-4-8 — highest keep-rate (most usable data per call), fastest, and traces fit the 4096-token student ceiling with room to spare.

claude-fable-5 was requested but excluded: 403 on both routes (AWS Bedrock Marketplace access not granted on this gateway account).

Caveats: n=40 is noisy; absolute keep-rates are depressed by NuminaMath difficulty + strict grading + format adherence, not just model capability — the relative ranking is the signal. For the real G build, rejection sampling with --max-attempts > 1 lifts the effective keep-rate.

Teacher assignments

Model G (solution generator): claude-opus-4-8.
Model V (critique writer; label already known from PRM800K → easier job): claude-haiku-4-5 (cheaper) is sufficient; use claude-opus-4-8 if budget allows.