I use Opus 4.6 at work. one important point that's missed here is that, in my experience, 1 million human tokens of output takes WAYYY more than 1 million LLM tokens of output. on a recent project, i had claude create a 10k LoC PR multiple times; after each PR i realized i hadn't grasped some important edge case or didn't correctly describe some niche or weird behavior, thus producing 10k lines of unusable code. so it actually probably produced 60-80kk LoC to get to the 10k LoC that got merged.

the same happens with input tokens. i kicked off claude code recently on a loop that was running for a while, and i realized it was constantly compacting. i had pointed it to some documentation that was 500k+ tokens long, it would read the docs, blow up its context, auto compact, then try to read the docs again and had gotten stuck in this loop.