# Muse Spark Open Enters Arena's Agent Arena for Public Testing By Simon Yoon Canonical URL: https://www.tokenpost.com/news/technology/32977 Published: 2026-10-16T02:57:42.000Z Updated: 2026-10-16T02:57:42.000Z Section: Technology > The model has 816 billion total parameters and a context window of one million tokens. Scores were pending when testing opened. Meta’s Muse Spark Open entered Arena’s Agent Arena on Oct. 15, the day its weights became available, giving developers a public venue to test a multimodal model built for software work and agent tasks. The model has 816 billion total parameters, with 42 billion active per token, and a context window of one million tokens. It accepts text, images, video and audio. It is designed for coding, extended assignments carried out by AI agents and tasks that require several linked reasoning steps. The Agent Arena evaluates how models perform in real exchanges: whether they complete a request, leave users satisfied and adjust when given direction. Scores were pending when the test opened. Meta first made Muse Spark available in April through a private API preview for select partners. Muse Spark Open is available through APIs from Baseten, Fireworks AI, Groq, Modal, Nebius, OpenRouter and Together AI. Its weights are available through Hugging Face and cloud model catalogs. The weights also support local use, including [deployment on Mac Studio clusters](). ## Links in this article - [deployment on Mac Studio clusters](https://www.tokenpost.com/news/technology/32912)