According to Anthropic, Claude Opus 5.5 achieves performance equivalent to Fable 5.1 at 40% lower cost and includes stricter safeguards against sandbox escapes and risky behaviors. The release received 778 points on Hacker News, though multiple users reported the model performed worse than expected and made more errors than prior versions despite unchanged usage patterns.
Topics #
Sources #
- Official[Read article](https://www.anthropic.com/claude-opus-5-5)
- Social[HN thread](https://news.ycombinator.com/item?id=49798699)
This intelligence is sourced automatically from public sources across the web and synthesised by the Prefactor AI pipeline. Stories are reviewed before publication.
source & further reading
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