Meta: Muse Spark Open

Meta: Muse Spark Open is a Meta model that accepts text, image, video, file, and audio input. It offers a 1,048,576-token context window and up to 943,718 output tokens, so long documents and lengthy generations can fit in a single request. It supports tool calling and reasoning. Structured output support is not listed, and despite the name, open-weights status is not confirmed in the available data. Pricing is $1.25 per million input tokens and $4.25 per million output tokens. Its blended benchmark score of 63.9 comes from a single independent benchmark (an AI index score of 64.1), so its standing rests on limited evidence. Shortlist it if your workload mixes audio, video, and documents, needs very long context, and relies on tools or reasoning. Run your own evaluations before committing, and confirm structured output and licensing terms with the vendor if either matters to you.