Radar — 10 Jul 2026

OpenAI ships the GPT-5.6 family — Sol, Terra and Luna
OpenAI's new GPT-5.6 models are rolling out across ChatGPT, Codex and the API, pitched squarely at agentic coding with adaptive reasoning and much lower token cost.
Independent read: GPT-5.6 Sol leads the Coding Agent Index at a third of the cost
Artificial Analysis' pre-release evaluation puts GPT-5.6 Sol second only to Claude Fable 5 on intelligence at ~1/3 the cost, and top of their Coding Agent Index when run in OpenAI's Codex harness.
agent-rules-books: SE classics distilled into drop-in agent rule sets
Fourteen software-engineering classics — Clean Code, Refactoring, DDD, DDIA and more — reworked into ready-to-load AGENTS.md rules for Codex, Cursor and Claude Code, in full/mini/nano sizes.