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OpenAI Codex (AGENTS.md)

Folder in every kit: codex/. Starter projects already have these files installed.

1. Copy codex/AGENTS.md and codex/.agents/ into your repo root.
2. Codex reads AGENTS.md automatically. Skills in .agents/skills/*/SKILL.md can be invoked by name or picked up implicitly. Skills with side effects ship an agents/openai.yaml that turns off implicit invocation.
3. Other AGENTS.md-aware tools can use the same file. Run a skill explicitly with $name or pick it from /skills. Writing your own? See how to write a SKILL.md that triggers.

Format notes

Codex stops reading project docs at 32 KiB by default (project_doc_max_bytes). Every kit's AGENTS.md is under 23 KB. Codex loads AGENTS.md files from the repo root down to the folder you start it in, not folders below it, so the kit's local-rules rule tells it to open the AGENTS.md next to auth or billing code before editing there. Run $record-decisions at the end of a session.