TechCrunch reports that Elon Musk's AI unit (now folded into SpaceX as "SpaceXAI") shipped Grok 4.5, which Musk is billing as a cheaper, more efficient alternative to other frontier models — explicitly describing it as "Opus-class," directly invoking Anthropic's flagship Claude Opus tier as the benchmark to beat.
The launch immediately drew a concrete three-way comparison: a same-day Hacker News post ("We made Grok 4.5, GPT-5.5, and Claude build the same apps") had all three frontier models build identical applications to compare real-world coding/agentic output — the most direct head-to-head available right now, rather than benchmark-table claims alone.