SpaceXAI Launches Grok 4.5: High-Speed Coding Agent to Rival Opus

The Breakdown

• 1SpaceXAI just dropped their newest model, Grok 4.5, and it is a massive deal if you run coding loops or automated agents. Elon Musk is calling it an 'Opus-class' model because it goes head-to-head with the heaviest engines out there, but runs way faster and costs a whole lot less.
• 2They trained this model on tens of thousands of Nvidia GB300 GPUs, dedicating a lot of effort to filtering out junk data and running reinforcement learning on hundreds of thousands of multi-step engineering tasks. The result is a system that can run complex, hours-long agent rolls without breaking.
• 3When it comes to actual numbers, Grok 4.5 is served at eighty tokens per second, making it faster than most flash models on the market. It also uses about four times fewer output tokens on coding benchmarks compared to Claude Opus, meaning you get your results faster and spend less.
• 4The pricing is seriously aggressive: it costs two dollars per million input tokens and six dollars per million output tokens, plus a heavy discount for cached inputs. That is a tiny fraction of what you would pay for other heavy reasoning models like Claude Opus.
• 5For builders and operators, this model is built directly into Grok Build and works out of the box with the SpaceXAI API and Cursor. It is incredibly good at writing code in languages like Rust and C/C++, or building entire functional web apps from a single prompt.
• 6This launch highlights a trend where powerful models are getting cheaper and faster, lowering the barrier for teams running autonomous software agents. By turning to these highly efficient API options, startups can run continuous background dev tasks without running up huge cloud bills.