Addy Osmani: Stop Using /init for AGENTS.md — Auto-Generated Context Files Decrease Agent Performance While Inflating Inference Costs 20%+

AddyOsmani.com·high signal

Two 2026 studies show LLM-generated AGENTS.md files hurt coding agent performance by 3% while increasing costs 20%+. The technique: treat AGENTS.md as a living list of non-inferable codebase smells (custom tooling, build commands, gotchas), not an auto-generated overview that duplicates what agents can discover on their own. A hierarchy of directory-scoped AGENTS.md files outperforms a single root file.