Meta releases Muse Spark Open model optimized for Apple’s Mac Studio
publishers 45articles 66first reported 6 Oct, 10:12 UTCdeveloping since 6 Oct · 21 editions
Meta released Muse Spark Open on Thursday, an open-weight artificial intelligence model designed for coding, software engineering and agentic tasks. Developers can download its weights and customize the model, which is available through Hugging Face and some API providers.
The model has 816 billion total parameters, with 42 billion active at a time, and supports a context window of up to 1 million tokens. Meta described it as a natively multimodal model suited to long-running tasks, multi-step reasoning and complex software development. The company claims it is the most capable U.S. open-weight model to date and said its benchmarks show stronger performance on some agentic and visual-reasoning tasks than leading Chinese models, including GLM 5.3 and Kimi K3. Those claims are based on Meta’s own testing.
Meta worked with Apple to optimize Muse Spark Open for Apple Silicon and the MLX machine-learning framework. The companies said it can run locally across two Mac Studio computers equipped with M5 Ultra chips and 512GB of unified memory each, or four machines with 256GB each. Local operation can give organizations greater control over their data and reduce reliance on cloud services, though the hardware requirements put the setup beyond most individual users.
The launch follows Meta’s release earlier in the week of its proprietary Muse Wonder and Muse Wonder Full frontier models. It also marks a rare public collaboration between Apple and Meta, whose executives said their teams had worked together for several months.
HOW THIS STORY WAS MADE
Written from 8 articles, 7 with the publisher's own text; 8 independent newsrooms once syndicated copies count as one; this version written 234 h after the record first saw the story; the editor kept it as written.
- Publishers
- 45
- Source articles
- 66
- Given to the writer
- 8, 7 with the article's own text
- Independent newsrooms
- 8
- This version written
- 234 h after the record first saw the story
- Second model (editor)
- kept as written
- Publication gate
- passed
- Human review
- none
WHAT THE EDITOR DID
The second model checked the writer's draft against the same sources and published it as written.
Written by a language model from the sources above, then checked by a second model that may only cut, attribute or correct. How it works →