[attentive]

23 mentions of "Claude" and not a single time mentioned the model he used.

[simonw]

Article was published July 30th, 2024 so I'm pretty sure he was using Claude 3.5 Sonnet.

(Though he works for Anthropic, so it's also possible he was using an unreleased internal model, maybe an early version of the forthcoming Claude 3.5 Opus.)