Models are updating so frequently now: Opus 5.5, GPT-6 Sol and Luna, MiMo-V2.6, Grok 4.7, and Step 5 Preview.

Grok 4.7. The model spends longer on complex tasks, self-verifies better and holds long context, plus it was trained to understand its own Grok Bot harness.

GPT-6 Sol and Luna. A fast and cheap tier to replace the GPT-5.6 family. Sol and Luna together cover the price-sensitive segment, while Astra remains OpenAI's flagship and most expensive model.

Claude Opus 5.5. The best model to date. Anthropic's successor to Opus 5: according to the company, on most tasks it matches the more expensive Fable 5.1, but costs 40% less. Sonnet 5.5 and Haiku 5.5 are promised "in the coming weeks".

Step 5 Preview
https://www.stepfun.com/step-5-preview
On September 20, Chinese company StepFun unveiled its new flagship for agentic work: an MoE with 600B total parameters and 27B active. Per their tests, strong in software engineering, above the Kimi K3 level. Fully open weights are promised by October 15 — for now there is only a placeholder repo on Hugging Face.

Top open-source model from Xiaomi
https://mimo.xiaomi.com/mimo-v2-6/article
Xiaomi released the MiMo-V2.6 series: the flagship MiMo-V2.6-Pro, the budget MiMo-V2.6-Flash, and MiMo-V2.6-Pro-UltraSpeed — the same Pro but with up to 20x faster output at the same quality. Xiaomi showed training live, streaming it during the release. Along with the models, the tech report, training environments, and all RL code were open-sourced.

Both main models are natively omnimodal (text, video, audio, images in one context) with a 1M-token window. Pro surpassed Kimi K3 and Qwen3.8 Max on the Artificial Analysis Intelligence Index, though it still falls short of closed models.

MiMo Code and MiMo Desktop
https://github.com/XiaomiMiMo/MiMo-Code
https://mimo.mi.com/docs/en-US/updates/feature/desktop
The terminal open-source coding assistant MiMo Code is a fork of OpenCode under MIT with subagent orchestration and a built-in free MiMo Auto channel. It now runs on V2.6 models. MiMo Desktop moved from early access to its first official release alongside V2.6. It is a desktop client for task agents, browser control, and interactive previews of results right in the session.

#mimo #claude #opus #openai #gpt6 #grok #stepfun #opensource