AI · 16 October 2026 · 6 min read
Meta put an 816-billion-parameter model on two Macs. The weights are the news, not a robot
Muse Spark Open activates about 42 billion parameters at a time and is meant to run locally on two Apple M5 Ultra Mac Studios. Meta and Apple both said so. Nobody has published what it does when the job is a gripper rather than a codebase.
Meta released the weights of Muse Spark Open on 15 October. The company describes it as an open-weight model with 816 billion parameters in total. Nvidia’s technical note on the release says it is a mixture-of-experts model that activates 42 billion of those parameters for each token, and that the context window is a million tokens. The Verge reported Meta’s claim that it is the first model of its class to run on a desk, using two Apple M5 Ultra Mac Studios and Apple’s MLX framework. Mark Zuckerberg said the weights run on the new Mac Studios because of work with Apple. John Ternus, Apple’s chief executive, replied that a model of that scale was running from the desk.
Axios reported that the weights are free to download under a licence that allows commercial use, and that the model is also offered through cloud providers. Nvidia’s note says the same weights, in a compressed form, are aimed at Nvidia’s own GB300 systems for coding agents: tool calls, long codebases, and inputs that include image, audio and video as well as text. Two machines on a desk and a rack of Blackwell chips are both “local” only in the sense that the lab in San Francisco is not in the loop. They are not the same electric bill.
A desk is not a robot
The interesting claim, for this desk, is that a model this large can leave the rented cloud and sit on hardware a company owns. That is the direction edge inference has been arguing for. It is not yet a claim about a machine that moves. Meta’s examples, as reported, are coding and long tasks on a computer. Apple’s examples are the Mac. Neither announcement says the model has closed a gripper, kept its balance, or survived a factory network that drops.
Two Mac Studios are also not a laptop. Meta’s “on your desktop” line means two of Apple’s largest studio machines, working together. A robotics group that wanted the same weights on the computer inside a humanoid would still have to show that the cut-down version, if one exists, does the job. Until someone publishes that run, this is a large open model with a local installation path, and a reminder that “open” and “small enough for a robot” are different sentences.