On Tuesday, Anthropic and OpenAI rolled out new artificial intelligence models with less than two hours between their announcements. Both debuts occurred just 10 days after their chief executives publicly advocated for an AI development slowdown.
Rather than pushing past their previous highest-performing models, however, both companies instead reduced their prices on this occasion. Furthermore, Elon Musk—who had also supported the initiative to slow down AI—offered his congratulations to Anthropic.
Anthropic Ships Opus 5.5 After Its AI Slowdown Call
At 16:31 UTC, Anthropic launched Claude Opus 5.5. The company stated that the model matches the performance of its Claude Fable 5.1 across most tasks while operating at a 40% lower running cost than Opus 5.
The 40% reduction is derived from Anthropic’s internal evaluations on standard workloads. List prices dropped by 20%, settling at $4 per million input tokens and $20 per million output tokens. Developers incur charges per token, which are the segments of text processed and generated by a model.
Opus 5.5 marks Anthropic’s first release since Dario Amodei, the company’s CEO, released an essay on September 12 encouraging labs to decelerate capability advancements. OpenAI CEO Sam Altman concurred with the sentiment, while Musk responded with “Dario is right,” as reported by BeInCrypto.
Nevertheless, Amodei’s essay left room open for new product rollouts.
“…pacing does not mean halting model training or technical progress, but ensuring companies take adequate time to align and safeguard their models,” wrote Amodei.
Anthropic noted that external evaluation groups METR and Frontier Design assessed Opus 5.5 prior to its publication.
OpenAI Answers With Cheaper GPT-6 Sol and Luna
OpenAI debuted GPT-6 Sol and GPT-6 Luna at 18:12 UTC. Both systems are faster, more economical alternatives built upon GPT-6 Astra, which continues to serve as the company’s flagship model.
The organization cut developer prices in half. Sol is now available at $2 per million input tokens, whereas Luna is priced at $0.10. Additionally, this 50% reduction is benchmarked against promotional pricing for GPT-5.6 rather than standard rates.
Both models are rolling out to paid ChatGPT subscribers immediately. Free-tier users gain access to test Luna through the desktop application.
Doubters expressed skepticism regarding the slowdown commitment from the outset. Investor Michael Burry characterized it as self-serving hype ahead of an IPO. Meanwhile, Morgan Stanley—an underwriter for Anthropic’s initial public offering—stated that the push does not alter corporate expenditure.
Neither AI lab has specified a timeline for releasing a model that surpasses its current flagship.