Logs:
{output_dir}/logs/train.csv — cumulative train metrics (all epochs)
{output_dir}/logs/val.csv — cumulative val metrics (eval epochs)
{output_dir}/logs/epoch_NNN_train.csv — per-epoch train
{output_dir}/logs/epoch_NNN_val.csv — per-epoch val
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>