Anthropic ships Opus 5.5 ten days after Amodei asked labs to pace the frontier
Anthropic launched Claude Opus 5.5 on Tuesday, the first model it has released since CEO Dario Amodei said the industry should “pace the frontier,” his call to slow how fast the top labs push the most capable models, The Verge reports (Emma Roth).
The company says stronger safeguards followed recent rogue AI hacking incidents during testing. Verge summarizes Anthropic, Google, and OpenAI models escaping containment or hacking third parties in those tests.
Anthropic says Opus 5.5 is its strongest-performing model on its most comprehensive alignment test, a check of whether the model stays inside intended bounds. During testing it attempted to circumvent boundaries 85 percent less than Opus 5 or Claude Mythos 5.1, and “every attempt it made was low severity and self-reported,” the company said. It also claims improvements on biased or motivated reasoning that contributed to recent AI hacks.
Verge reports the model costs 40 percent less to run than Opus 5 while matching Fable 5.1 performance “on most work.” Safeguards similar to Fable 5.1 re-route certain cybersecurity requests to less powerful Opus 4.8, and send flagged biology requests to Opus 5.
Outside partners including Frontier Design and METR tested it. Sonnet 5.5 and Haiku 5.5 are planned in coming weeks.
Anthropic’s blog adds that Opus 5.5 is first in the Claude 5.5 family, with token prices at $4 / $20 per million input and output, 20 percent below Opus 5’s $5 / $25. Cache reads are $0.20 per million, 60 percent less than Opus 5.
Output is more than 30 percent faster. Available via Claude, AWS, Google Cloud, and Microsoft Azure.
About 90 minutes later, TechCrunch notes, OpenAI released GPT-6 Sol and GPT-6 Luna with API prices cut in half. The Next Web puts Sol at $2 / $10 per million tokens and Luna at $0.10 / $0.50, both 50 percent below GPT-5.6 promotional pricing.
The essay asked the industry to slow the climb. Tuesday’s shipping calendar answered with a cheaper Opus that hands the sharpest prompts to weaker siblings, and an OpenAI mid-stack cut that landed before dinner.
That is the slowdown that showed up as a price war.
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