Muse Spark 1.3 is Meta's September 2, 2026 Spark—1M context, $1.25/$4.25. Rank looks high because it is benchmaxxed: tuned to crush short evals, not to hold a long assistant run. Helpfulness, instruction following, and comprehension look strong on one-shot work. Give it hours of tools and it drifts. We timed it ourselves, and it is much faster than Artificial Analysis reports. Empathy is cooler. Creative writing still pays a thinking tax: usable drafts, not literary. Use it for a sharp first answer, not a days-long assistant.