#Anthropic

AIAnthropic has released Claude Haiku 5.5, available now across all platforms including Amazon Web Services, Google Cloud, and Microsoft Azure. The post links to Anthropic's announcement page for further details.

AIAnthropic says Claude Haiku 5.5 shows major improvements across almost all of its alignment evaluations compared with Claude Haiku 4.5. The post reports far fewer instances of misaligned behavior in the new model.

AIAnthropic's Haiku 5.5 is built for high-volume, cost-sensitive work such as summaries and classification. It can serve as a subagent alongside Claude Opus 5.5 and Sonnet 5.5 on coding tasks. It is also fast enough for live customer support and browser use.

AIThe Department of Defense's Chief Digital and Artificial Intelligence Office runs the Tradewinds program, which grants "post-competitive" status to AI vendors based on videos of five minutes or less. That status can let government buyers use other transaction agreements and sometimes make awards in less than a week. OpenAI, Anthropic, and Google are listed as participants, though none commented.

AIElon Musk says SpaceX will use the best back-end model for each task on Grok Bot, including Claude Opus 5.5, MidJourney, Suno, and other leading APIs. Matt Shumer calls this extremely good news for bot users.

AIMistral released Mistral Large 4 "Le Chonk", a 1T-parameter (49B active) multimodal model, with open weights planned in about three weeks. Google rolled out Nano Banana 2.1 across Gemini, AI Studio, and the Gemini API, and released EmbeddingGemma 2, a 740M-parameter open multimodal embedding model under Apache 2.0. OpenAI launched the Decisions API in beta with gpt-6-luna, returning typed answers 10x faster than the Responses API.

AIElon Musk says SpaceX will use the best back-end model for each task, including Claude Opus 5.5, Midjourney, Suno, and other leading APIs. The main post is only an eye emoji, so its own content adds nothing beyond the quoted note about Grok's routing.

AIGrok Bot will now use the best backend model for each task, including Claude Opus 5.5, MidJourney, Suno, and other leading APIs. The change is framed as choosing whatever is most likely to produce the best outcome for users.

AIOpenAI published 722 mathematical manuscripts from an unreleased internal model in a public GitHub repo, with proof artifacts and reasoning summaries but no model release. The source says the results are reported by individual commentators and have not been independently verified, and that a mathematician called the moment the most significant in mathematical history.

AIAnthropic released Claude Haiku 5.5, which it calls its cheapest, fastest, and most capable small model. It costs around 75% less to run than Haiku 4.5 and is aimed at high-volume, cost-sensitive tasks such as summaries and classification. The release also cuts Sonnet 5.5 cache read prices by 50%, and the model is available on AWS, Google Cloud, and Microsoft Azure.

AIAnthropic released Claude Haiku 5.5, which scores 43 on the Artificial Analysis Intelligence Index, up 26 points from the last Haiku release. Pricing is $0.10/$0.50 per 1M input/output tokens up to 100k tokens, rising to $0.50/$2.50 above that, but at max effort it uses about 162k output tokens per Intelligence Index task, roughly 3x GPT-6 Luna.

Why it matters: The benchmark shows Haiku 5.5 scores well but uses far more output tokens than GPT-6 Luna, so cost per task matters beyond list price.

AIAnthropic added build-eval and hillclimb commands to its claude-api skill for designing evaluations and iteratively improving applications against them. The article covers eval design principles, including production-representative tasks, headroom and low variance, and guards against overfitting through train/test splits. Two examples report results: a customer support benchmark where cost fell to under half while accuracy rose, and a claude-api skill eval that rose from 66% to 88%.

Why it matters: The article gives a concrete workflow for designing evals and hillclimbing without overfitting, with two worked cost and performance examples that show the tradeoffs.

AISpeakers at The Curve, a Berkeley AI conference, discussed limiting how intelligent large language models can become, amid concerns over recursive self-improvement. Proposed approaches include Anthropic's responsible scaling policy, limits on compute and model copies, and restrictions on using frontier models for AI research. The column notes such enforcement tools do not yet exist and that the Trump administration opposes such restrictions.

AIAnthropic launched Claude Haiku 5.5, which it describes as the cheapest, fastest, and most capable small model it has released, aimed at high-volume, cost-sensitive tasks. Max and Team plans now include monthly API credits for running their own apps and agents on the Claude Platform, rolling out over a few days. Users claim the credits by linking a Claude Console organization in Settings > Billing for Max or Organization settings > Billing for Team.

Why it matters: The notes name a new small model and a credit change for Max and Team plans, with the claim path, which matters for teams budgeting API use.

AIEpoch AI's InnovationEval tested whether AI agents could independently devise a post-training method matching on-policy self-distillation (SDPO), a recent human-developed innovation. GPT-5.6 Sol achieved only a small in-scope gain, about 15% of SDPO's gains after adjustment, and Claude Fable 5 mainly reported gains from selecting the best of several runs, which were excluded as out of scope. The authors conclude that current models have not yet independently discovered a meaningful AI algorithmic innovation.

Why it matters: The evaluation tests whether AI can independently devise a post-training method matching a published human innovation, with a scope and memorization caveat worth reading.

AIand those files can also open inside Claude. In Google Workspace, Claude appears in a sidebar next to the open file, reads its contents, and edits it in place, with the option to approve each edit before it is applied.

AIAnthropic's Thariq says Claude will increasingly use cloud-based "brains" while operating on users' computers through "local hands." He points to a Latent Space podcast discussion on how this is being implemented in Claude Code.

AIBoris Cherny says he used Opus 5.5 with Lean to formally verify the Claude Agent SDK, with a couple of short prompts producing 16 PRs fixing bugs and race conditions. He also reports that TLA+ works well, sometimes combined with Lean to find data flow, concurrency, and state management issues. The post links to his actual prompts as another example.

AIAnthropic's Boris Cherny says Claude works best when prompted like a coworker, with a clear goal and no heavy scaffolding. He says prompts now matter most for stating the desired task, the effort level, and how Claude should verify its result, whereas prompts mattered more in the Sonnet 3.5 era.

AIAnthropic is expanding its Cyber Verification Program to give verified security professionals broader access to its most capable models. Through the program, they can use Claude Mythos 5.1, Opus 5.5, and Sonnet 5.5 with safeguards designed for defensive work. New tiers will also allow authorized offensive work such as penetration testing and red-teaming.

AIClaude Code v2.1.292 adds a --marketplace option to claude plugin install, which adds the marketplace if needed and then installs the plugin from it. The release also adds an effort parameter to the Agent tool and fixes several security issues, including permission prompts bypassed for network (UNC) file reads and a sandboxed read path that could return files outside approved access.

AIAnthropic's Lydia Hallie says users can still claim a one-time bonus credit for Claude Code cloud sessions until October 7 by running /claim-credit. Cloud sessions run Claude Code on a fresh VM per task, letting several run at once even after the laptop is closed.

AIAnthropic's ClaudeDevs account says Pro or Max plan subscribers on September 23 can still claim a one-time bonus credit for cloud sessions by running /claim-credit in Claude Code by October 7 at 11:59pm PT. Cloud sessions draw on this credit first before counting toward plan limits, and the credit expires November 4.

AIAnthropic's ClaudeDevs says Claude Code cloud sessions run each task on a fresh VM, so users can start several at once. The sessions keep running after the user closes their laptop. A field guide covers seven suitable workflows and how to connect GitHub.

AIAnthropic's Claude can now open Google Docs, Sheets, and Slides beside the chat, either from a pasted Google file link or a request for a new file, so users and Claude can edit together. Access follows existing Google sharing permissions. The feature is in beta on all paid plans.

AINathan Lambert argues that policy debates on open-weight model cyber risks lack nuance, because banning open models may not reduce risk and could weaken American competitiveness. He says closed frontier APIs have been tied to most documented cyber attacks, and that restricting open models while closed models keep advancing could widen the offense-defense gap. He also argues that Chinese labs' safety practices are shaped by their own government and society, and that the claimed risk of models like Claude Mythos has been overstated.

AIClaude for Google Workspace is in public beta on all paid Claude plans, adding a sidebar to Google Docs, Sheets, and Slides. It can read the open file, edit text, build formulas, pivot tables, charts, and slides, and it asks for approval before changes unless the user chooses "Accept all edits." New Docs, Sheets, and Slides connectors in beta let Claude create and edit Google files from the chat, with access matching existing Google sharing permissions.

Why it matters: The source specifies how Claude edits Docs, Sheets, and Slides in place and where users keep control, which clarifies the practical workflow change.

AIComcast and Booz Allen used Claude Mythos Preview to find vulnerabilities that arise from interactions across code, configuration, and deployment rather than single-file bugs. Comcast identified a critical authentication flaw across 258 systems and about 170 million lines of code before any exploitation was observed. Booz Allen reported that one analyst reviewed eight production systems across 138 repositories in twelve days, a review its team estimated would have taken several months without the model.

Why it matters: The case studies show how security teams validate and remediate model-found exploit chains, a workflow relevant to anyone managing large codebases.