Meta's closed Muse Ember nearly matches Claude Haiku 5.5 at about a third of the cost
Meta has released Muse Ember, the newest and smallest model in its proprietary Muse family from Meta Superintelligence Labs. It succeeds Muse Spark. On Terminal-Bench 4.0, a benchmark of command-line tasks, Ember scored 40.9% using the open-source mini-swe-agent harness. VentureBeat reports that this nearly matches Claude Haiku 5.5 at about one-third of the estimated per-task cost. Vals AI says Ember is the cheapest model on its index at $0.15 per test and outperforms both Haiku 5.5 and GPT-6 Luna, and Meta says it leads on intelligence per dollar.
Ember reflects Meta's shift in strategy. The company has expanded its closed Muse lineup instead of relying only on the open-weight Llama family. Meta says its frontier Muse Wonder model reaches top agent-reasoning benchmarks with an order of magnitude less compute than Llama 4 Maverick, and its standalone Muse app has passed 2.5 million downloads. The broader company is under cost pressure: Meta cut about 8,000 jobs, roughly 10% of its workforce, and canceled 6,000 planned hires while budgeting $135–145B for AI capital spending.
The benchmark comparison has drawn criticism. Developers noted that the Ember result used mini-swe-agent while Haiku's comparable score used Claude Code, a different harness. Harnesses strongly affect agent benchmark scores, so the two numbers are not directly comparable. VentureBeat itself called the comparison rough. Developers want results run on the same harness and same codebase.
The bigger backlash concerns openness. A top r/LocalLLaMA thread complained that Muse weights remain closed despite Mark Zuckerberg's earlier promises about open source. Small, cheap models are exactly what the local-inference community wants to run on its own hardware, so keeping Ember closed is especially frustrating to them. Watch whether Meta releases Ember weights, whether independent same-harness benchmarks confirm the cost claims, and whether Llama gets any new release at all.