Meta's Muse Spark series has shown rapid iteration, with version 1.3 launching September 2, 2026, via the Meta Model API and Muse Code after 1.2 in early August. The update emphasized long-horizon agentic workflows, coding benchmarks like DeepSWE, and efficiency gains with fewer tool calls, while maintaining a 1M-token context window and multimodal capabilities. This builds on earlier entries where prior versions achieved competitive Text Arena rankings against models like Claude Opus and Gemini. Traders see Meta Superintelligence Labs' momentum—coupled with paid API expansion and frontier positioning—as supporting a high-likelihood strong debut for 1.4+, though exact leaderboard thresholds depend on Meta's evaluation focus versus product optimization.