SpaceXAI and Cursor Launch Grok 4.5: First Jointly Trained Coding and Agentic Model
On July 8, 2026, SpaceXAI (SpaceX's AI division) and coding platform Cursor (Anysphere) launched Grok 4.5, marking their first collaborative model release since SpaceX announced its landmark $60 billion stock acquisition of Cursor in June 2026.
Grok 4.5 is a mixture-of-experts (MoE) model trained jointly using SpaceXAI's massive compute infrastructure and trillions of tokens of Cursor's real-world developer interaction data. Unlike preceding coding-only specialists like Composer 2.5, Grok 4.5 was built to handle complex, long-running agentic tasks across broader professional domains including data science, finance, and legal work.
The model relies heavily on reinforcement learning (RL) in highly complex environments to train the system to use tools, recover from errors, and verify its own work. To make the model highly competitive, SpaceXAI priced the base model aggressively at $2 per million input tokens and $6 per million output tokens, directly undercutting rival models like Claude Opus and GPT-5.6 on inference costs.
The release of Grok 4.5 represents the first tangible product of SpaceX's $60 billion acquisition of Cursor, demonstrating how the aerospace conglomerate plans to integrate Cursor's developer ecosystem directly with its AI division.1
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An instance of The era of model-neutral developer tools has ended. — SpaceX's vertical integration of Cursor's developer workflow into its hardware and model divisions marks the end of model-neutral developer environments. ↩︎