Troubleshooting Codex emits a one-line PR body with no detail. Force a structured description (before/after, why, test plan) with a PR template, AGENTS.md, and a CI gate; plus the Codex Cloud button caveat.
Prompt Library Inherited a 200-file codebase? 12 prompt templates to infer naming, layering, error-handling, and dependency conventions before you write a single new line.
Troubleshooting Codex writes `getUserById` when your codebase uses `findUserById`. Codify each convention as rule + a canonical example file in AGENTS.md, then verify it loaded.
Troubleshooting Tab and Composer use different naming / formatting / patterns than your repo — training prior beats retrieval; anchor explicitly.