Musk said reinforcement learning is continuing to improve the model and that "Grok Build," xAI's coding-agent harness, is being refined daily. He framed the SpaceX and Tesla deployment as an internal proving ground before any wider release.

xAI's Grok 4.5, a 1.5 trillion parameter model built on V9 with Cursor data, enters private beta at SpaceX and Tesla with performance rivaling Anthropic's

Musk said reinforcement learning is continuing to improve the model and that "Grok Build," xAI's coding-agent harness, is being refined daily. He framed the SpaceX and Tesla…

xAI launches Grok 4.5 in private beta with SpaceX and Tesla, powered by a 1.5 trillion parameter V9 model that rivals Anthropic's Claude Opus.

Elon Musk announced Grok 4.5's private beta, asserting its performance rivals or surpasses Anthropic's Opus, with ongoing reinforcement learning enhancements.

Elon Musk said that SpaceX had deployed "a few dozen" top Starlink and Starship engineers and Cursor staff to work on the AI model.