# Meta releases Muse Spark Open, an 816B-parameter model built for agents

> Source: <https://runtimewire.com/article/meta-releases-muse-spark-open-816b-model>
> Published: 2026-10-15 17:11:36+00:00

# Meta releases Muse Spark Open, an 816B-parameter model built for agents

**Alexandr Wang's team is releasing the weights for coding and long-horizon tasks, with local operation requiring two M5 Ultra Mac Studios or substantial GPU memory.**

        By [Ryan Merket](https://runtimewire.com/author/ryan-merket)
        · Published 
        · Updated 

Primary source: [X](https://x.com/alexandr_wang/status/2110778736434184611)

## Why it matters

Meta is putting Wang's frontier-model work into developers' hands as downloadable weights, but the hardware demands and API-specific license threshold distinguish access from unrestricted deployment.

Meta released the weights for [Muse Spark Open](https://research.meta.ai/blog/muse-spark-open) on October 15th, giving developers access to an 816-billion-parameter multimodal model designed for coding and long-running agent tasks. [Alexandr Wang](https://x.com/alexandr_wang), who leads Meta's AI effort, described it as the most capable US open-weight model to date; that ranking is Meta's claim, not an independently established result.…