Muse Spark 1.2 is the coding-focused foundation model released by Meta Superintelligence Labs on August 5, 2026, co-trained with the Muse Code terminal agent it powers. It has a 1,048,576-token context window and accepts text, image, video and PDF input. On Meta's published charts it scores 82.9% on Terminal-Bench 2.1, 59.3% on DeepSWE v1.1 and 70.6% on Meta's internal coding benchmark, up from 76.2%, 53.0% and 68.3% for Muse Spark 1.1, placing it second behind Claude Opus 5 on all three. Pricing is $1.25 per million input tokens and $4.25 per million output tokens, with a data-contributor tier more than ten times cheaper. Meta publishes no parameter count or architecture details.
Parameters
Undisclosed
Context Window
1M
License
Proprietary
Release Date
2026-08-05
Benchmark Performance
AA Intelligence Index
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LMArena Elo
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HLE
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ARC-AGI-2
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SWE-bench Verified
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GPQA Diamond
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MMLU-Pro
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LiveCodeBench
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AIME 2025
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MATH-500
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API Pricing
Input Price (per 1M tokens)
$1.25
Output Price (per 1M tokens)
$4.25
Billing Mode: per 1M tokens
Strengths
- •Near Opus-tier agentic coding at a fraction of the cost (82.9% on Terminal-Bench 2.1)
- •Jointly trained with the Muse Code harness for long-horizon, multi-turn workflows
- •1,048,576-token context with text, image, video and PDF input
Weaknesses
- •Places second behind Claude Opus 5 on all three of Meta's own coding benchmarks
- •Closed weights; no self-hosting or fine-tuning
- •No published parameter count or architecture details, limiting independent verification
Use Cases
- •Autonomous multi-step coding agents over large repositories
- •Multi-file change and refactoring automation
- •Long-running background engineering agents