New frontier and open models, releases, benchmarks and what changed.
Anthropic released Claude Haiku 5.5 at $0.10 per million input tokens and $0.50 output for prompts up to 100,000 tokens, a tenth of Haiku 4.5's price. Above that line the deal changes, so check your prompt lengths before you celebrate.
Google released Nano Banana 2.1 on October 6, an update to its Flash-tier image model that, by Google's own evaluations, holds multi-character scenes together far better. If you make images with people in them or infographics with real text, test it this week.
OpenAI published 722 manuscripts in 372 result families on GitHub on Tuesday, produced mostly by an unreleased internal model, and not all are formally verified. The bottleneck in AI math has moved from finding proofs to checking them.
Mistral opened a public preview of Mistral Large 4 on Tuesday, a mixture-of-experts model with about 1 trillion parameters and 49 billion active, and promised weights by the end of October. The API is a preview. The weights are the launch.
Reflection AI introduced Beam on Monday, a 501-billion-parameter mixture-of-experts model with 23 billion active, and promised Apache 2.0 weights later in October. Until the weights ship, it is a waitlist and a claim about efficiency.