OpenAI, Perplexity, DeepSeek, Anthropic, RSI

Send us Fan Mail Monday. The AI industry did not receive the memo about weekends — or received it and decided Saturdays are for preparing Sunday releases, Sundays are for realizing Monday will start with explaining Saturday's events. Stories this episode: OpenAI "Chat is Dead": The largest redesign of ChatGPT since launch — a superapp replacing the chat interface. Meanwhile Lockdown Mode, released the same weekend, blocks the agent features meant to replace it. Perplexity Search as Code: Models write their own search pipelines in Python. OpenAI and Anthropic beaten on benchmarks, token costs down 85%. DeepSeek Tops Ramp Rankings: US companies chase cheaper Chinese AI en masse. Security economist warns about direct data transfer risks. Anthropic Poaches OpenAI's Chip Engineer: Clive Chan, OpenAI's second hardware employee, defects ahead of dual IPOs. Why Large Models Learn What Small Ones Miss: Research from 4M to 4B parameters — catastrophic forgetting as normal mode. Fix is frequency, not scale. ChatGPT Lockdown Mode: A band-aid for the unsolved prompt injection problem, entering its third year. Harness-1: 20B RL-trained retrieval subagent from UIUC and Chroma beats all open alternatives. datasette-agent-edit 0.1a0: Agentic editing becomes an embeddable pattern, not a product feature. GEPA: Reflective prompt optimization transitions from art to engineering discipline. HN: Are We Letting LLM Companies Take All the Values? A 25-point societal discussion. Every Monday brings a new redesign, new API, new talent raid. The industry moves by inertia, driven by the fear of falling behind. "For good" in this industry only lasts until the next rebranding.