📝 TL;DR 📝 SpaceXAI released Grok 4.5 on July 8, its first model since going public and acquiring the AI coding tool Cursor for $60 billion. Elon Musk is calling it "Opus-class," roughly comparable to Anthropic's Opus 4.7, at a fraction of the price: $2 per million input tokens and $6 per million output, versus Opus 4.8's $5 and $25. Independent testing backs the cost story more than the capability claim: Grok 4.5 lands fourth on a real-world agentic benchmark, behind the newest Claude models, but uses roughly four times fewer output tokens on coding tasks, which meaningfully changes total cost per completed job. 🧠 Overview 🧠 This is SpaceXAI's first release since two major structural changes: going public, and acquiring Cursor, one of the most widely used AI coding tools, in a deal reportedly valued at $60 billion. Grok 4.5 was trained jointly with the Cursor team, and the positioning reflects that lineage directly. This is not being marketed as a general chatbot upgrade. It is aimed squarely at coding, agentic workflows, and knowledge work, the same territory Anthropic's Opus and Claude Code, and OpenAI's newly launched GPT-5.6 family, are competing in. The launch also landed on an unusually crowded day for frontier AI. OpenAI rolled out GPT-5.6 publicly the same week, after a staggered release tied to government review. For the first time in months, all three major US AI labs, OpenAI, Anthropic, and SpaceXAI, have current flagship-tier models publicly available at roughly the same moment. 📜 The Announcement 📜 Musk introduced Grok 4.5 directly on X: "It is an Opus-class model, but faster, more token-efficient and lower cost," later clarifying, "Our internal assessment is that Grok 4.5 is roughly comparable to Opus 4.7, but much faster." That comparison is notable for what it does and does not claim: Opus 4.7 is a prior Claude generation, not Anthropic's current frontier model. SpaceXAI's own published benchmark charts show Grok 4.5 beating Opus 4.8 on two of four coding benchmarks and losing on the other two, with Anthropic's Fable 5 leading most of those charts outright. The company has been fairly candid about this positioning: it says Grok 4.5 beats some rival models on speed, price, and performance, but not the largest, latest models from those same competitors.