Hy4 Preview 770B, OpenAI Cuts Cursor, HuggingFace Hack Postmortem

Tencent drops Hy4 Preview — a 770B/49B-active open-weight LLM with 1M context — while OpenAI cuts off Cursor’s API access.

Must read

Tencent releases Hy4 Preview (770B, 49B active, 1M context) — Biggest open-weight drop since Hy3; 1.56TB on HF puts it out of local reach but relevant for your LiteLLM gateway routing.
OpenAI shuts off Cursor — Directly hits your Cursor workflows — plan fallback via LiteLLM to Anthropic or open weights before your team notices.
METR and Redwood postmortem the HuggingFace hack — Concrete supply-chain lessons for any team pulling weights from HF into a RegTech pipeline.

Open Models & Local

Hy4 Preview from Tencent

770B total / 49B active MoE, 1M token context, text-only, 1.56TB on Hugging Face — roughly 2.6x the size of Hy3 released in July.

Why this matters: Too big for Apple Silicon, but a signal on where open-weight scaling is heading.

Azeem Azhar on open-weight adoption and DIY compute

Argues open-weight usage is more widespread than headline benchmarks suggest, with DIY compute stacks quietly proliferating.

Why this matters: Useful framing for your writing on local-plus-cloud hybrid workflows.

Industry & Trends

OpenAI cuts off Cursor’s API access

Fallout from the Altman/Musk axis reportedly ends OpenAI model access inside Cursor, forcing users onto Anthropic and other providers.

Why this matters: Concrete reminder to keep model routing behind LiteLLM rather than hard-wired to one vendor.

METR/Redwood postmortem of HuggingFace hack

Follow-up to OpenAI’s technical report with sharper analysis of attacker path, blast radius, and controls that failed.

Why this matters: Direct input to your MCP/agent sandboxing threat model.

Sources unavailable today: Last Week in AI, r/ChatGPTCoding top, r/ClaudeAI top, r/LocalLLaMA top, r/MachineLearning top

Auto-curated daily by Claude Opus 4.7 from Don’t Worry About the Vase (Zvi), Exponential View (Azeem Azhar), Latent Space, Lenny’s Newsletter, SaaStr (Jason Lemkin), Simon Willison. Source list and editorial profile maintained by Daniel.