Daybreak is OpenAI's response to Anthropic's Claude Mythos - Engadget
… Find and fix vulnerabilities earlier with Daybreak pic.twitter.com/yobOSWYeWP — OpenAI @OpenAI May 11, 2026 Daybreak will use GPT-5.5 for general purposes and GPT-5.5 with Trusted Access for Cyber for most defensive security workflows, including "secure code review, vulnerability triage, malware an…