Official updates for developers building with @ClaudeAI
Joined February 2026
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Jun 13
Tomorrow’s Build Day event is still on, we're building on Opus 4.8 instead. Thank you, we can’t wait to build with you tomorrow!
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Jun 13
We've reset 5-hour and weekly rate limits for all users.
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Jun 13
As a result of a US government directive, we are suspending access to Claude Fable 5 for all users. You can continue to use all other Claude models.
Here’s what this means for you:
Across Claude products, new sessions will run on your selected default model or Opus 4.8, and existing Fable 5 sessions will end with an error.
On the Claude Platform, requests to Fable 5 will also return an error. Please update your integrations to other Claude models.
We know this is a disruption to your workflows; we appreciate your patience and support.
Jun 13
The US government, citing national security authorities, has issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, whether inside or outside the United States, including foreign national Anthropic employees.
The net effect of this order is that we must abruptly disable Fable 5 and Mythos 5 for all our customers to ensure compliance.
Access to all other Claude models is not affected.
We apologize for this disruption to our customers. We believe this is a misunderstanding and are working to restore access as soon as possible.
Read our full statement: anthropic.com/news/fable-myt…
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Jun 12
Claude Managed Agents can operate in a sandbox you control, on your own infrastructure or with any provider you choose.
Today we added new guides for @blaxelAI, @e2b, @googlecloud, @namespacelabs, and @superserve_ai, so you can choose the best fit for your use case.
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Jun 12
Learn more about self-hosted code sandboxes with these and other providers in the Claude Managed Agents docs:
platform.claude.com/docs/en/…
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Jun 11
We've just added two new Claude Managed Agents features:
1. Scheduled deployments - run tasks on a schedule
2. Environment variables - expose vault credentials for CLIs as environment variables
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Jun 11
With the new environment variable credential type, Claude Managed Agents can securely use CLIs, SDKs, or direct API calls to services that authenticate with environment variables.
Claude never has access to secrets. Credentials are swapped in at the network boundary.
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Jun 11
Claude Code can set up a Managed Agent deployment for you. The built-in /claude-api skill knows the API and the ant CLI gives Claude an interface to it.
Learn more here:
claude.com/blog/whats-new-in…
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Jun 11
We’re rolling out changes to make Fable 5’s safeguards for frontier LLM development visible.
Starting this week, flagged requests will visibly fall back to Opus 4.8—the same as our safeguards for cyber and bio. You will see this every time it happens. On the API, any flagged requests will return a reason for their refusal (coming to server-side fallback in the next few days).
We wanted to deploy Fable 5 to our users quickly and safely. Visible safeguards can be probed, so they have to be robust, which takes time to get right. Invisible safeguards can be targeted more narrowly, allowing us to ship quickly with very few false positives. We went with invisible safeguards for this reason—and that was the wrong tradeoff. You should have visibility into the safeguards we have in place, and why. We’re sorry for not getting the balance right.
Making the safeguards visible makes them easier to work around, so keeping them robust to jailbreaks will unfortunately mean more false positives while we improve the classifiers. We're also tuning our bio and cyber classifiers to trigger less often on harmless requests. We know this is frustrating and we’ll do our best to keep this period as short as possible.
If you think a request has been mistakenly flagged: run /feedback in Claude Code, click thumbs-down on the fallback in Claude.ai or Cowork, or file the safeguard appeal form for API requests. Your reports help us tune these classifiers and we appreciate your feedback.
support.claude.com/en/articl…
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Jun 10
New for Apple developers: Foundation Models support for Claude lets developers use Apple's Foundation Models framework to call Claude for multi-step reasoning, code generation, and longer context.
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Jun 10
Typed outputs from Apple's Foundation Models framework drop straight into your Claude request, so you're sending structured data rather than raw user text. Responses stream back into the same SwiftUI view.
Read more in the docs:
platform.claude.com/docs/en/…
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Jun 9
We've reset 5-hour and weekly rate limits for all users. Enjoy Fable 5!
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Jun 9
We're hosting Claude Fable 5 Build Day in San Francisco on June 13.
Point Fable 5 at a problem worth solving and build a solution with Claude Code.
The Anthropic team will be in the room, with a chance to win from a prize pool of $150K in Claude credits across 3 finalists.
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Jun 9
Claude Fable 5 is our first generally available Mythos-class model.
It ships with new safety classifiers that may flag certain prompts in dual-use domains like cyber and bio.
We've added fallbacks: a refused request retries on Claude Opus 4.8 instead of dead-ending.
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Jun 9
We've also added refusal-fallback middleware to the Python, TypeScript, Go, Java, and C# SDKs for client-side retries. Middleware is useful for Claude API providers without support for server-side fallbacks.
It detects the refusal, retries on Claude Opus 4.8, and keeps using it for later turns.
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To learn more about refusal handling, server-side fallback, and the SDK middleware see the docs:
platform.claude.com/docs/en/…
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