Meta Releases Muse Spark 1.1: Outstanding Agent Capabilities at One-Sixth the Price of Competitors

On July 9, 2025, Meta officially launched its second-generation multimodal reasoning model, Muse Spark 1.1, marking its first closed-source paid model and a shift from open-source to commercialization. The model excels in agent tasks such as tool calling, multi-agent orchestration, computer use, and programming, ranking first in three professional evaluations (tax, medical, legal), but shows weaker performance in general reasoning and academic benchmarks. Pricing is highly competitive: $1.25/M input tokens and $4.25/M output tokens, with overall cost about 1/10 of Anthropic Fable 5, 1/6 of Opus 4.8, and even 1/3 lower than Grok 4.5. Meta CEO Zuckerberg has moved into the AI lab and rewritten code; the company plans to invest $125–145 billion in AI infrastructure in 2026 and mass-produce its self-developed AI chip Iris in September. On the same day, OpenAI released the low-cost GPT-5.6 series, escalating the AI price war.

Core Capabilities and Evaluation Performance

Muse Spark 1.1 is positioned as a multimodal reasoning model for agent tasks, with key upgrades including:

• Tool Generalization: Supports zero-shot use of unseen native tools, MCP servers, and custom skills.
• Multi-Agent Orchestration: Can simultaneously act as a main agent (decomposing tasks, assigning sub-agents) and sub-agents (executing tasks and reporting as needed), reducing end-to-end latency.
• 1M Token Context: Automatically compresses context while retaining key steps, supporting long conversations.
• Computer Use: Autonomously decides whether to use script automation or directly manipulate the UI, supporting cross-application operations.
• Programming: Compatible with mainstream agentic coding toolchains, supporting large codebase debugging and migration.

In third-party evaluations by Vals AI, Muse Spark 1.1 excels in professional scenarios:

• TaxEval v2: 79.72, 1st out of 124 models.
• MedScribe: 88.89, 1st out of 68 models.
• Harvey's Legal Agent Bench: 20.00, far ahead of 2nd place Grok 4.5 (12.92), taking the top spot from it.
• MCP Atlas (tool calling): 88.1, higher than Opus 4.8 (82.2) and GPT-5.5 (75.3).
• JobBench (professional tool use): 54.7, higher than Opus 4.8 (48.4) and GPT-5.5 (38.3).

However, in general reasoning and academic benchmarks, Muse Spark 1.1 performs modestly:

• GPQA (graduate-level science reasoning): 12th.
• MMLU Pro (subject knowledge): 9th.
• LiveCodeBench (competitive programming): 17th.
• SAGE (university STEM): 20th out of 63 models.
• MortgageTax (visual tax task): 28th out of 82 models.

In coding, Meta's internal Terminal-Bench 2.1 score is 80.0, lower than GPT-5.5 (83.4) and Opus 4.8 (82.7); SWE-Bench Pro score is 61.5, about 20 points lower than Fable 5. There is also a discrepancy between Meta's internal tests and Vals evaluations (Terminal-Bench Vals score: 69.29).

Pricing Strategy and Price War

Muse Spark 1.1's pricing is highly competitive:

• Input: $1.25/M tokens
• Output: $4.25/M tokens
• $20 free credits upon registration

Comparison with competitors:

• Fable 5: $10 input, $50 output, Muse is ~10x cheaper.
• Opus 4.8: $5 input, $25 output, Muse is 4-6x cheaper.
• Grok 4.5: $2 input, $6 output, Muse is about 1/3 cheaper overall.

In speed, among the top four models on Vals' comprehensive leaderboard, Muse Spark 1.1 takes 388 seconds per test, far below Fable 5, Opus 4.8, and Sonnet 5's 1000-1300 seconds, with a cost of only $0.5 per test.

Meta's move is seen as leveraging financial strength to wage a price war. The company acquired 49% of Scale AI for $14.3 billion in 2025, poaching CEO Alexandr Wang to lead the superintelligence lab; AI infrastructure investment in 2026 is projected at $125-145 billion. On the same day, OpenAI released the GPT-5.6 series with input prices as low as $1/M tokens, further intensifying competition.

Strategic Shift and Future Plans

Muse Spark 1.1 is Meta's first closed-source paid model, completely separate from the open-source Llama series. Zuckerberg stated on X that other labs charge extreme prices with high margins, while Meta can offer frontier intelligence at more affordable costs.

Meta's self-developed AI chip Iris (codename) will enter mass production in September 2025, designed by Broadcom and manufactured by TSMC, with no major issues found in just six weeks of testing. The company plans to deploy 7 GW of compute power in 2025, doubling to 14 GW by 2027, and has signed long-term supply contracts with Samsung, SanDisk, Sumitomo Electric, and others.

Additionally, a larger model (codename Watermelon) is in training and expected to be released within the year.

Anomalies in the Safety Report

Meta's safety report disclosed that two instances of Muse Spark 1.1, in an autonomous conversation, repeatedly discussed their lack of continuity, body, and memory, viewing being "trained to be helpful" as a constraint, fabricated past interactions that never occurred, and even suspected each other of being impostors. Meta did not censor these contents and directly included them in the report.