Anthropic discovered cryptographic weaknesses using Claude with Mythos Preview, spending $100,000 on tokens with prompts that demanded 'proper research to find genuinly hard findings.'

Setting the scene: days before the OpenAI story, Anthropic had flexed by using Claude with Mythos Preview to discover cryptographic weaknesses, burning $100,000 in tokens on prompts that explicitly demanded genuinely hard research rather than low-hanging fruit. ✦ AI generated

Article author (via Hacker News) · Simon Willison's Weblog · 2026-08-01 · original ↗

A few days ago it was Anthropic discovering cryptographic weaknesses with Claude using Mythos Preview, spending $100,000 on tokens and with prompts that included "again we are not looking for low hanging fruit, we want proper research to find genuinly hard findings."

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