Mike Krieger (@mikeyk) header
Mike Krieger (@mikeyk) profile picture

Building at Anthropic Labs @anthropicai. Before: CPO at Anthropic, co-founder & CTO of @instagram and @artifact_news

37.760571,-122.387567
Joined November 2006
Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)Photo by Mike Krieger (@mikeyk)
Very fun to see the team both ship new native artifact types like sheets and whiteboards today, and also open up the platform for developers to build full experiences into Claude as well.
Replying to @claudeai
Also new: with interactive connectors, you can now open the full version of a tool inside Claude. Work in Adobe, Atlassian, and Box beside your conversation. Make changes yourself, or ask Claude to make them with you. Rolling out on web and desktop.
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Claude Fable 5.2 and Mythos 5.2 are out today! They’re super sharp to work with. On complex problems you can really feel the extra intelligence; researchers working with Fable 5.2 solved two problems from theoretical physics. Fable is also a great thought partner on strategy, paired with Opus 5.5 for a lot of my work. Can't wait to see how you use Fable 5.2 to bring your big ideas to life!
Introducing Claude Fable 5.2 and Claude Mythos 5.2, designed to tackle the most daunting technical challenges. They’re capable collaborators on ambitious projects in many fields, and show improvements in areas like coding, reasoning, and vision.
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We're opening Claude Duet today as a research preview, starting with a waitlist. It's our take on giving everyone a trusted partner with your work. I've been using it for a few weeks, at work and at home. It drafted questions for a fireside chat, watched Slack over the weekend so I could log off, and told me about the new @nealstephenson book — and then ordered it from my local bookstore once I asked. We've found Opus 5.5 was our first model with the judgment to be proactive in the right ways. Here's what that's looked like.
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Another model joins the 5.5 family with the small but mighty Haiku 5.5! It’s built for speed and efficiency, and costs 75% less than Haiku 4.5. Opus does the heavy thinking, Haiku does the high-volume work, and together you get more done for less. Happy shipping!
Introducing Claude Haiku 5.5: the cheapest, fastest, and most capable small model we’ve ever released. On average, it costs around 75% less to run than Claude Haiku 4.5.
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Sonnet 5.5, the second release in the 5.5 family, is out! It’s 30%+ faster than Sonnet 5 and up to 30% cheaper for most work.
Introducing Claude Sonnet 5.5, the second model in the Claude 5.5 family. It’s a clear upgrade over Sonnet 5, runs more than 30% faster, and costs up to 30% less for most work.
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I still reach for Opus 5.5 for most work, but Sonnet 5.5 is a great complement. I love its design skills and it's great for building features — I use it to make Artifacts often now. Try it out and let us know what you think!
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Go try out Opus 5.5, which we launched today! It leads in coding and knowledge work, and it’s a great writer. It performs at the level of Claude Fable 5.1 for most tasks, and costs 40% less to run than Opus 5.
Introducing Claude Opus 5.5, the first model in our new Claude 5.5 family. It performs at the level of Claude Fable 5.1 for most tasks, and costs 40% less to run than Opus 5.
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We cut API pricing to $4/million input and $20/million output tokens (20% less than Opus 5) and cache reads are 60% cheaper too. For subscribers, we raised five hour limits and you get a banked rate limit reset to use whenever you need it most.
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Omid and the team did great work on this one. Most of my Claude Desktop work these days is in these new-style projects and I've really enjoyed how easy it is to kick off a bunch of work while still having a coordinator Claude responding quickly
Super excited to show the world Projects!! We've been building this for the last few months and it has become my new daily driver. A few tips for getting the most out of it 🧵
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Also new today: Claude Docs, Claude Slides and Claude Design are now available in every conversation, powered by a revamped Artifacts platform. Ask for a design, deck, or document. Get back something you can edit, download, and take anywhere. Try it out for yourself and let us know what you think.
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Claude Cowork and Chat are now one Claude, starting today. The most common thing we hear: people aren't sure which product to start with. That friction gets in the way of getting the best from what these models can do. I've been on the unified version for a few weeks and really enjoy it. Claude does the deciding about how to get there, while I get to keep my thinking on the work itself. Let us know what you think! We'll be getting it dialed in over the coming weeks.
Claude Cowork and chat are merging into one Claude. Ask a quick question or hand over a report, and Claude takes it from there, even after you close your laptop. If something's unclear, Claude asks—you keep the final say. Rolling out to Pro and Max over the next few weeks.
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We launched Claude Fable 5.1 this morning! Fable models are built for complex, multi-step work that runs on its own, and Fable 5.1 sets a new standard across coding, knowledge work, and long-running problem-solving tasks.
We’re introducing Claude Fable 5.1 and Claude Mythos 5.1. They're the world’s most advanced models for coding and knowledge work.
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It's also more honest as it works. Give it a target and it works until it gets there, and when it's stuck it says so instead of reporting success. It’s the same price as Fable 5 ($10/$50), and we've cut the price of cache reads 75% to $0.25/MTok on the API.
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Opus 5 quickly became my daily driver both at work and on the weekends. It can work for hours on complex tasks, and I've found it consistently gets to the bottom of tricky tasks. I also had some fun building some games with it 🧵
Introducing Claude Opus 5. It's a thoughtful and proactive model that comes close to the frontier intelligence of Fable 5 at half the price.
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In this game, the "era" of a game is adjustable in real time, which you need to do to solve puzzles — for example, a bridge that's solid in the 1980's becomes hollow when you fast forward through time: youtube.com/watch?v=zfhBeZHz…
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New today as Claude Cowork starts rolling out to web and mobile: Chat and Cowork now share one home tab on web and desktop — one sidebar, one search, and one place for your Projects & Artifacts. Keep an eye out for even better Chat + Cowork integration soon, too.
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One of my favorite things we've shipped recently — used it today to visualize a tricky set of experiment gates & logic, and communicate that to the team.
Artifacts in Claude Code are now also available on Pro and Max plans. Ask for an artifact, Claude writes the code, publishes it live to claude.a‍i, and updates it in real time while it keeps working. Pages are private to your account and fully self-contained.
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Our Labs team worked on this along with the Claude Code team — as Claude's work gets deeper and more independent, I've found really valuable to have it explain its thinking and outputs using Artifacts; try asking it to diagram its work next time you're working with it.
New in Claude Code: Artifacts. Interactive pages built from your session, like a PR walkthrough or a living project dashboard, shared with your team at a private link. Available in beta on Team and Enterprise plans.
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Claude Fable 5 is out today. The first Mythos-class model everyone can use & the first model I hand off whole projects to. This weekend I built a self-maintaining, proactive media tracker for myself, over 2 days with Fable taking large chunks at a time
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It's state of the art on nearly every benchmark we tested and the lead grows the longer the task. Made safe for general release: cyber & bio requests fall back transparently to Opus 4.8 and 95%+ of sessions never see one. $10/$50 on the API, in paid Claude plans today.
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Been building with Claude Opus 4.8 (out today!) for a couple weeks and it's already the model I reach for first. The best part is how much I can just let it run. It's more honest about its own work, flags what it's unsure of, & catches flaws in its code before handing it back.
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We're also shipping Dynamic Workflows in Claude Code, which lets Claude spin up a team of subagents that work, verify, and report back; I've used them for migrating entire codebases from one language to another, or completing complex projects (works best in auto mode)
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Claude Opus 4.7 is out! Handles ambiguous, multi-step work even better than 4.6. Cursor's internal bench cleared 70%, up from 58% on 4.6. Notion saw a 14% lift on their evals with a third of the tool errors 🔨
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Excited for this one — everything you need to ship production agents at scale, without having to spend months on infra work.
Introducing Claude Managed Agents: everything you need to build and deploy agents at scale. It pairs an agent harness tuned for performance with production infrastructure, so you can go from prototype to launch in days. Now in public beta on the Claude Platform.
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Always great to chat with @danshipper ! Love what he and the team at @every are cooking up, we could have talked for hours.
The rules of professional product development are being rewritten in real time. - PMs and designers can ship software as easily as engineers. - Software is no longer just built for humans—it’s also built for agents as first-class citizens. To better understand how we build products in this world, I invited Mike Krieger (@mikeyk) on @every’s AI & I podcast. Mike cofounded Instagram and is now a member of the technical staff at Anthropic, co-leading Anthropic Labs, their internal incubator for experimental products. He's been at the frontier of two transformative technology waves: mobile/social and now agent-native software. We discussed: - How to build a truly agent-native product. The best products today, like Claude Code, allow users to do things that their creators never intended. But that requires hard trade-offs between freedom and safety/reliability for frontier products, an issue that Mike's team is learning how to solve. - What's different about building now versus building Instagram. At Instagram, it took months to hit dead ends and learn what to cut. Now, that cycle runs in hours. - The trap of building too much, too fast with agents. You can go from idea to a nearly-shipped product in a day, but that process doesn’t give you the incremental feedback that used to tell you what not to build. The models are great at adding features, but can create a product that lacks coherence. - How Anthropic Labs structures product teams. New product experiments are led by only two people, usually a product manager or designer paired with an engineer. Mike says bigger teams tend to be too slow because of coordination costs. - Why you need to throw out your product and start over every three to six months. AI progress means most of your harness will be outdated quickly—the best teams build this into their product strategy. And much more! You should watch this one. Timestamps Introduction: What's gotten easier—and what hasn't—about building products in the age of AI: Why vibe coding creates "indoor trees": How rewrites have become a normal part of the development process: What "agent native" product design means: How Mike's labs team is structured and the cofounder model: The best signal for a product bet is someone with "break through walls" conviction: Navigating enterprise customers while keeping pace with rapid AI change: OpenClaw, personal agents, and the product question defining 2026:
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