Daily Research Brief 2026-07-29

📊 Token usage: estimated from retrieval and writing scale.

Covers the latest AI research, open source and industry moves, updated daily.

Editor’s Note

Two signals converging into one thread: open-source models are overtaking closed-source on ‘scale ceiling’ for the first time. Kimi K3 (2.8T params, fully open-sourced 07-27) hit the top-3 most-popular open models in Hugging Face history within 48 hours.

1. Latest arXiv Papers

1. CHILL-Harness: Counterfactual Harness Learning for Efficient Reasoning in Long-Horizon Agents — https://arxiv.org/abs/2607.25825

2. Speculate While You Reason: Teaching Agents to Predict Their Next Tool Call via Joint Agent-Speculator RL — https://arxiv.org/abs/2607.25816

3. AngelSpec: Towards Real-World High Performance Inference with Speculative Decoding — https://arxiv.org/abs/2607.25852

4. Are Prompt Optimizers Blind? Cross-Modal Visual Feedback for Automatic Prompt Optimization — https://arxiv.org/abs/2607.24354

5. Layered Scenario-Driven LLM Control — https://arxiv.org/abs/2607.22651

6. RP-OPSD: Resolution-Privileged On-Policy Self-Distillation for Multimodal Large Language Models — https://arxiv.org/abs/2607.24447

7. Many-body Tipping Dynamics of ChatGPT-like AIs — https://arxiv.org/abs/2607.25279

8. Subspace-Aligned Rewiring (SAR): 0.58% Parameters Raise Reasoning Instead of Lowering It — https://arxiv.org/abs/2607.03065