Devin, Cognition's AI software engineering platform, has re-enabled Claude Fable 5 across all its surfaces: Devin Cloud, Devin Desktop, and Devin CLI. The timing is significant. As of June 30, the export controls on Fable 5 and Mythos 5 were lifted, with Fable 5 becoming available again starting July 1 to users globally on the Claude Platform, Claude.ai, Claude Code, and Claude Cowork. Devin is one of the first coding agent platforms to restore the integration.
Claude Fable 5 was originally made available in Devin across Cloud, Desktop, and CLI on June 9, but as of June 12, access was removed following Anthropic's announcement and the US government directive. That directive came fast and hit hard: on June 12, the US government applied export controls to Fable 5 and Mythos 5, requiring Anthropic to restrict access to foreign nationals. Because the order took effect immediately and there was no reliable way to verify nationality in real-time, Anthropic suspended access to both models for all users.
What triggered the ban , and why it was lifted
Government officials enacted the restriction after researchers at Amazon documented a method to bypass the safety controls of Fable 5, causing the model to identify software vulnerabilities and supply exploitation code. The irony? Anthropic's testing confirmed that many less capable models , including Claude Opus 4.8, GPT-5.5, and Kimi K2.7 , could identify the same vulnerabilities as Fable 5 did in the report.
To get Fable 5 restored as quickly as possible, Anthropic trained an improved safety classifier that targets and blocks the jailbreaking behavior that led the government to apply export control to the models. The AI can now block the technique described by Amazon in more than 99% of cases, though the trade-off is a more sensitive AI with more false positives on legitimate development or debugging tasks.
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