New on the Engineering Blog: Quantifying infrastructure noise in agentic coding evals. Infrastructure configuration can swing agentic coding benchmarks by several percentage points—sometimes more than the leaderboard gap between top models. Read more:

New Engineering blog: We tasked Opus 4.6 using agent teams to build a C compiler. Then we (mostly) walked away. Two weeks later, it worked on the Linux kernel. Here's what it taught us about the future of autonomous software development. (1/2)

New Engineering blog: We tasked Opus 4.6 using agent teams to build a C compiler. Then we (mostly) walked away. Two weeks later, it worked on the Linux kernel. Here's what it taught us about the future of autonomous software development. (1/2)

Ads are coming to AI. But not to Claude. Keep thinking.

Claude is built to be a genuinely helpful assistant for work and for deep thinking. Advertising would be incompatible with that vision. Read why Claude will remain ad-free: https://www.anthropic.com/news/claude-is-a-space-to-think

You can now connect Slack to Claude on Pro and Max plans. Search your workspace channels, prep for meetings, and send messages back to keep work moving forward—without leaving your conversation with Claude. Get started: http://claude.com/connectors/slack

Apple's Xcode now has direct integration with the Claude Agent SDK, giving developers the full functionality of Claude Code for building on Apple platforms, from iPhone to Mac to Apple Vision Pro. Read more: https://www.anthropic.com/news/apple-xcode-claude-agent-sdk

A.A.Murakami create immersive, multi-sensory installations that merge technology with ephemeral natural phenomena like fog, bubbles, and plasma. In their latest piece, Claude serves as a studio collaborator. Video: https://twitter.com/claudeai/status/2018471168974684303

New Anthropic Research: Disempowerment patterns in real-world AI assistant interactions. As AI becomes embedded in daily life, one risk is it can distort rather than inform—shaping beliefs, values, or actions in ways users may later regret. Read more:

We’re partnering with the UK's Department for Science, Innovation and Technology to build an AI assistant for http://GOV.UK. It will offer tailored advice to help British people navigate government services. Read more about our partnership: https://www.anthropic.com/news/gov-UK-partnership

Now available on the Free plan: Claude can create and edit files. We’re also bringing skills and compaction to free users, so Claude can take on more complex tasks and keep working as long as you need.

Your work tools are now interactive in Claude. Draft Slack messages, visualize ideas as Figma diagrams, or build and see Asana timelines.

Claude in Excel is now available on Pro plans. Claude now accepts multiple files via drag and drop, avoids overwriting your existing cells, and handles longer sessions with auto compaction. Get started: http://claude.com/claude-in-excel

Claude Cowork is now available for Team and Enterprise plans.

Since release, Petri, our open-source tool for automated alignment audits, has been adopted by research groups and trialed by other AI developers. We're now releasing Petri 2.0, with improvements to counter eval-awareness and expanded seeds covering a wider range of behaviors.

New on the Anthropic Engineering Blog: We give prospective performance engineering candidates a notoriously difficult take-home exam. It worked well—until Opus 4.5 beat it. Here's how we designed (and redesigned) it: https://www.anthropic.com/engineering/AI-resistant-technical-evaluations

We’re publishing a new constitution for Claude. The constitution is a detailed description of our vision for Claude’s behavior and values. It’s written primarily for Claude, and used directly in our training process. https://www.anthropic.com/news/claude-new-constitution

Claude can now securely connect to your health data. Four new integrations are now available in beta: Apple Health (iOS), Health Connect (Android), HealthEx, and Function Health.

The VS Code extension for Claude Code is now generally available. It’s now much closer to the CLI experience: @-mention files for context, use familiar slash commands (/model, /mcp, /context), and more. Download it here: https://marketplace.visualstudio.com/items?itemName=anthropic.claude-code

Tino Cuéllar, President of the Carnegie Endowment for International Peace, has been appointed to Anthropic’s Long-Term Benefit Trust: https://www.anthropic.com/news/mariano-florentino-long-term-benefit-trust

We're partnering with @TeachForAll to bring AI training to educators in 63 countries. Teachers serving over 1.5m students can now use Claude to plan curricula, customize assignments, and build tools—plus provide feedback to shape how Claude evolves.

New Anthropic Fellows research: the Assistant Axis. When you’re talking to a language model, you’re talking to a character the model is playing: the “Assistant.” Who exactly is this Assistant? And what happens when this persona wears off?

We're publishing our 4th Anthropic Economic Index report. This version introduces "economic primitives"—simple and foundational metrics on how AI is used: task complexity, education level, purpose (work, school, personal), AI autonomy, and success rates.

New in Claude Code on the web and desktop: diff view. See the exact changes Claude made without leaving the app.

Since launching our AI for Science program, we’ve been working with scientists to understand how AI is accelerating progress. We spoke with 3 labs where Claude is reshaping research—and starting to point towards novel scientific insights and discoveries.

We're supporting @ARPA_H's PCX program—a $50M effort to share data between 200+ pediatric hospitals on complex cases, beginning with pediatric cancer. The goal is to help doctors learn from similar cases and shorten the care journey from years to weeks. (1/2)

We’re expanding Labs—the team behind Claude Code, MCP, and Cowork—and hiring builders who want to tinker at the frontier of Claude’s capabilities. Read more: https://www.anthropic.com/news/introducing-anthropic-labs

AI is ubiquitous on college campuses. We sat down with students to hear what's going well, what isn't, and how students, professors, and universities alike are navigating it in real time. (1/3)

Introducing Cowork: Claude Code for the rest of your work. Cowork lets you complete non-technical tasks much like how developers use Claude Code.

To support the work of the healthcare and life sciences industries, we're adding over a dozen new connectors and Agent Skills to Claude. We're hosting a livestream at 11:30am PT today to discuss how to use these tools most effectively. Learn more:

New Anthropic Research: next generation Constitutional Classifiers to protect against jailbreaks. We used novel methods, including practical application of our interpretability work, to make jailbreak protection more effective—and less costly—than ever.

New on the Anthropic Engineering Blog: Demystifying evals for AI agents. The capabilities that make agents useful also make them more difficult to evaluate. Here are evaluation strategies that have worked across real-world deployments.

Some delightfully specific things people are building with Claude Code lately.

Starting at midnight PT tonight, all Pro and Max plans have 2x their usual usage limits through New Year's Eve.

We’re releasing Bloom, an open-source tool for generating behavioral misalignment evals for frontier AI models. Bloom lets researchers specify a behavior and then quantify its frequency and severity across automatically generated scenarios. Learn more: https://www.anthropic.com/research/bloom

As part of our partnership with @ENERGY on the Genesis Mission, we're providing Claude to the DOE ecosystem, along with a dedicated engineering team. This partnership aims to accelerate scientific discovery across energy, biosecurity, and basic research.

People use AI for a wide variety of reasons, including emotional support. Below, we share the efforts we’ve taken to ensure that Claude handles these conversations both empathetically and honestly. https://www.anthropic.com/news/protecting-well-being-of-users

Claude in Chrome is now available to all paid plans. We’ve also shipped an integration with Claude Code.

Skills are now available on Team and Enterprise plans. We're also making skills easier to deploy, discover, and build.

You might remember Project Vend: an experiment where we (and our partners at @andonlabs) had Claude run a shop in our San Francisco office. After a rough start, the business is doing better. Mostly. Video: https://twitter.com/AnthropicAI/status/2001686747185394148

How will AI affect education, now and in the future? Here, we reflect on some of the benefits and risks we've been thinking about. Video: https://twitter.com/AnthropicAI/status/2001070081829212274

We’ve shipped more updates for Claude Code: - Syntax highlighting for diffs - Prompt suggestions - First-party plugins marketplace - Shareable guest passes

We’re opening applications for the next two rounds of the Anthropic Fellows Program, beginning in May and July 2026. We provide funding, compute, and direct mentorship to researchers and engineers to work on real safety and security projects for four months.

MCP is now a part of the Agentic AI Foundation, a directed fund under the Linux Foundation. Co-creator David Soria Parra talks about how a protocol sketched in a London conference room became the open standard for connecting AI to the world—and what comes next for it. (1/2)

Today we’re shipping 3 more updates for Claude Code: - Claude Code on Android - Hotkey model switcher - Context window info in status lines

We're releasing more upgrades to Claude Code CLI: - Async subagents - Instant compact - Customer session names - Usage stats

New research from Anthropic Fellows Program: Selective GradienT Masking (SGTM). We study how to train models so that high-risk knowledge (e.g. about dangerous weapons) is isolated in a small, separate set of parameters that can be removed without broadly affecting the model.

We’ve shipped three new updates for Claude Agent SDK to make it easier to build custom agents: - Support for 1M context windows - Sandboxing - V2 of our TypeScript interface

Anthropic is donating the Model Context Protocol to the Agentic AI Foundation, a directed fund under the Linux Foundation. In one year, MCP has become a foundational protocol for agentic AI. Joining AAIF ensures MCP remains open and community-driven.

We’re expanding our partnership with @Accenture to help enterprises move from AI pilots to production. The Accenture Anthropic Business Group will include 30,000 professionals trained on Claude, and a product to help CIOs scale Claude Code. Read more: