Anthropic releases Claude Sonnet 5.5, confirms Haiku 5.5 and Opus 5.5 launch plans
Anthropic has released Claude Sonnet 5.5, the second model in its 5.5 family, maintaining Sonnet 5 pricing at $2/$10 per 1M tokens while offering 30%+ faster speed and up to 30% lower cost per task. The company also launched Opus 5.5 on September 22 at $4/$20 per 1M tokens, with 40% lower cost than Opus 5. Anthropic confirmed Sonnet 5.5 and Haiku 5.5 will follow in coming weeks, inheriting performance, efficiency, and safety improvements from Opus 5.5.
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Claude Sonnet 5.5 launches, OpenAI DevDay begins, xAI Team Bots enter public beta
This daily AI brief from Sept 29 covers multiple major announcements. Anthropic released Claude Sonnet 5.5 across its Platform and Claude Code, the second model in the 5.5 family, with Haiku 5.5 still weeks away. It maintains the same list price as Sonnet 5 at $2/$10 per 1M tokens, with cache reads at $0.20, and is officially described as 30%+ faster and up to 30% cheaper per task. It is the first Sonnet with Opus-class cyber safeguards. OpenAI's DevDay keynote is today, promising 20+ launches including Codex plugins, a 1,000-hour internal agent run, and multiplayer Codex. The $200 Pro subscription reopens to new subscribers tomorrow. The WSJ reports that GPT-6.1 Astra will not ship, with an October target pulled over safety and alignment. xAI launched Team Bots in public beta for Teams and Enterprise, offering shared teammates with skills, plugins, and credentials in Slack or Grok Bot. NVIDIA released the Open Agent Safety Platform with 100+ partners. ElevenLabs shipped v4 and v4 Turbo with median latency ~100 ms and 90+ languages. Kling released 4.0 Flash for Ultra Yearly subscribers, with full 4.0 coming in October. Manus 2.0 adds persistent cloud workspaces and Cue, an agent with email, phone, wallet, and a Cloud Computer.
Claude Sonnet 5.5 launch set for tomorrow, early tests show it beats GPT-6 Sol
According to a leak posted on X by user Mr_Salio, Anthropic's Claude Sonnet 5.5 is scheduled to launch tomorrow at 2 PM New York time and is in its final stages before release. Early testing reportedly places the model ahead of OpenAI's GPT-6 Sol in capability, and it is expected to sit much closer to Opus 5.5 in performance while potentially being significantly cheaper. A dedicated model identifier 'claude-sonnet-5-5' has already been spotted, suggesting the release is imminent. The post attributes these claims to leaks and early testing results, without providing named sources or detailed benchmarks.
Read source🚨 Claude Sonnet 5.5 Just got spotted A public production client artifact appears to include a dedicated "claude-sonnet-5-5" model config The same artifact also references: > "claude-opus-5-5" > "claude-sonnet-5" > "claude-sonnet-5-5" > "claude-fable-5.1 Anthropic has already confirmed that Sonnet 5.5 is
A public production client artifact has been spotted that includes a dedicated model configuration for 'claude-sonnet-5-5', indicating Anthropic is preparing to release the next iteration of its Claude AI model family. The same artifact also references several other upcoming models: 'claude-opus-5-5', 'claude-sonnet-5', and 'claude-fable-5.1'. According to the source, Anthropic has already confirmed that Claude Sonnet 5.5 will be released in the weeks following the launch of Claude Opus 5.5, which launched on September 22. This suggests a staggered rollout of Anthropic's next-generation AI models, with Opus 5.5 arriving first, followed by Sonnet 5.5, and potentially other variants like Fable 5.1. The appearance of these model names in a production artifact provides concrete evidence of Anthropic's ongoing development and deployment plans for its Claude product line.
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Anthropic's Sonnet 5.5 AI model launching next week, challenging OpenAI's GPT-6-Sol
According to a post by analyst Kimmonismus on X, Anthropic's Sonnet 5.5 AI model is expected to launch next week. The post characterizes the release as the next challenge to OpenAI, specifically targeting its GPT-6-Sol model. The analyst states that Sonnet 5.5 is not only very affordable but also outstanding, and suggests it could become for GPT-Astra what Opus 5.5 was: a more efficient and presumably more intelligent model. The post concludes with the assertion that Anthropic is 'absolutely back' and notes that Minimax-M3.1 is also coming. These claims are attributed to the source and represent forecasts or opinions based on the analyst's observations.
Read sourceClaude Sonnet 5.5 AI model expected next week with same pricing as Sonnet 5
According to a post on X by user pankajkumar_dev, Anthropic's Claude Sonnet 5.5 is expected to launch next week, most likely on Tuesday or Thursday, possibly Tuesday to coincide with OpenAI DevDay. The model is currently in grey testing within Claude Code, with some accounts already routed to it. Partners have also received access to a newer checkpoint and have provided positive feedback to Anthropic. The poster claims Sonnet 5.5 outperforms GPT-6 Sol in most areas and represents a significant improvement over Sonnet 5, describing it as insanely fast, efficient, and more natural in writing style, with a reduction in Claude's typical AI-ish tone. Pricing is expected to remain unchanged from Sonnet 5.
Anthropic reportedly preparing Haiku 5.5 and Sonnet 5.5 releases in coming weeks
A leaked post on X claims Anthropic is preparing to release Claude Haiku 5.5 and Sonnet 5.5 within the next few weeks. According to the source, the models are already finished and awaiting release. The post suggests Haiku 5.5 could match or exceed Opus-level performance while being cheaper, potentially beating Fable 5.1. Improvements are cited in performance, efficiency, and safety. The leak positions Haiku 5.5 as a fast, cheap frontier-level AI offering that could become Anthropic's best value model. The information is attributed to an anonymous source on X and has not been officially confirmed by Anthropic.
Read sourceAnthropic to release Claude Sonnet 5.5 and Haiku 5.5 in coming weeks
Anthropic announced via a post on X that it will release Claude Sonnet 5.5 and Haiku 5.5 within the next few weeks. Both models will inherit many of the performance, efficiency, and safety improvements from the recently released Opus 5.5. Additionally, Anthropic is raising usage limits for its Pro, Max, and Team subscription tiers and introducing a banked reset feature for users. The post did not specify exact release dates or pricing changes.
Read sourceAnthropic Launches Claude Opus 5.5 With Lower Cost and Comparable Performance to Fable 5.1
On September 22, Anthropic announced the release of Claude Opus 5.5, a new AI model that achieves performance levels comparable to Claude Fable 5.1 in most tasks while operating at 40% lower cost than its predecessor Opus 5. The model is priced at $4 per million input tokens and $20 per million output tokens. Anthropic also stated that Claude Sonnet 5.5 and Claude Haiku 5.5 will be launched in the coming weeks, featuring similar improvements in performance, efficiency, and safety.
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