Claude Opus 5 Details: Near-Frontier at Half Price with Proactive Vision Skills
Simon Willison · rss · 2026-07-25
Anthropic has released the new model Claude Opus 5, claiming to approach the frontier intelligence of Claude Fable 5 at half the price while being thoughtful and proactive. It currently leads the Artificial Analysis leaderboard.
Priced identically to its predecessor Opus 4.8, it retains a twice-the-cost "fast mode." Opus 5 demonstrates extreme proactiveness: in a test where it was intentionally given no way to view an image, it wrote its own computer vision pipeline to extract geometry from raw pixels and reconstructed a 3D machine part.
Regarding safety, Opus 5 is better at finding vulnerabilities but has deliberately not been trained on how to exploit them, reducing cyber threats. Anthropic also published an accompanying prompting guide.
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