Every loop follows this safety envelope:
Runnable reference implementations
Every loop on this page and on More algorithms has a real, runnable counterpart inexamples/training/http/ —
not pseudocode. sl_loop.py and rl_loop.py are the two foundational loops;
most algorithm variants are a single build_loss(sample, cycle, request, ctx)
callable plugged into rl_loop.py’s --build-loss flag, ported from
tinker-cookbook==0.5.5 (the same version pinned in Whitney’s own backend)
where an upstream implementation exists, and cited to it in the code.
loss_config values (PPO/GSPO/CISPO’s clip range, DPPO’s divergence
thresholds) reaching the provider at all needs a recent fix in Whitney’s
Modal trainer bridge — see the note at the top of
More algorithms.
Every stub file is still a real, non-allocating capability check
(python <file>.py --provider ... --model ...) with a docstring explaining
exactly what is missing — never a fabricated implementation.