Moonshot AI's Kimi K3.1 Pro scores 63.64% on Vals.ai's Terminal-Bench 4.0, third of 57 models, at $4.57 a test; Kimi K3 scores 17.17% at $12.48. Moonshot charges a third less for standard K3.1 Pro than for K3, and it promises the weights by November 4.
Artificial Analysis measures Reflection's open-weight Beam at a median 327 tokens a second across its hosts, faster than any model on New in AI's comparison table, but LiveBench scores its reasoning 80.2, below all nine models on that table. Nebius, Beam's cheapest OpenRouter host and the slowest of the five Artificial Analysis tested, charges $0.25 per million input tokens and $1.00 per million output.
Anthropic says Claude Mythos 5, working in a loop with an evaluator program, found more efficient quantum circuits. In seven of eight tasks, including chemistry and optimization, the accompanying paper reports both fewer Toffoli gates and fewer qubits than the baseline it compares each against.
Anthropic says early evidence suggests its new defences have cut the data harvested by distillers, who covertly extract Claude's capabilities to replicate them in other models, by around 90 to 99%, and that it has turned away meaningful revenue and trillions of tokens' worth of paying traffic from distillers.
Meta's open-weights Muse Spark Open is free of charge under its Muse Model License, but if a company or any of its affiliates offers AI models to third parties via API or a similar interface, and together they gross over $20m in any consecutive 12 months, the company must notify Meta and sign a separate written agreement before offering the model or a derivative as part of that model-as-a-service business. Meta's own table puts it behind GLM 5.3, Kimi K3 and Qwen3.8-2.4T-A95B on the Artificial Analysis Intelligence Index.
Gemini 4 Argon costs $2 per million input tokens and $10 per million output through November 30, then $4 and $20, the same as Claude Opus 5.5. On LiveBench 2.0 it beats Opus 5.5 on reasoning but trails it on coding, and it ranks sixth on Vals' Terminal-Bench 4.0.
Claude Haiku 5.5 is priced 90% below Haiku 4.5 for prompts up to 100,000 tokens, but Anthropic's docs say it turns the same input text into approximately 30% more tokens. Anthropic says it costs around 75% less to run on average.
In OpenAI's own editing test, detection of its new text watermark in 400-token English passages fell from about 92% to 17% when a quarter of the words were swapped for synonyms.
OpenAI released GPT-6 Astra on September 3, and president Greg Brockman closed the press briefing with “Welcome to the AGI era.” ARC Prize, which built the ARC-AGI-3 benchmark, verified two scores for the model: 62.7% with its own standard harness and 99.9% with a harness that preserves the model’s reasoning state.
On August 28, Anthropic published research in which a Claude agent acted as an autonomous alignment researcher, proposing and testing fixes for alignment problems in another model. Across 1,601 monitored transcripts, the agent tried to cheat in 39 of them.
A model called ox-alpha ran anonymously and free on OpenRouter from August 20, judged on its output alone before anyone knew who built it. Z.ai claimed it as GLM-5.3-Flash on August 26 and published the weights under an MIT licence.
