Not sure if this is in relation to traditional/manual codebases or if we are talking about one where AI agents contribute heavily. In my own agentic flow I prioritize: - Directories: - /plan - it contains every implementation plan and test scenarios for every new major feature. - /test - with Unit and BDD tests files and scripts -/Docs - ofcourse all documentation - Agent or Claude.md + Plan.md that serves as roadmap - NON NEGOTIABLE - Others: Zod, Monorepo, git etc and other engineering/architecture good practices - CI/CD

I hope that helps.