Project Rules in depth: encode standards once

Project RulesVersion-controlled instructions in the repo that every Cursor agent interaction inherits, so standards are encoded once. Press Enter for the full definition. are how you stop re-explaining your codebase to the model on every prompt. Write your style, test and architecture standards once. They live in the repo, version-controlled and every agent interaction in that scope inherits them automatically.

The mechanism: rules live under .cursor/rules/ as scoped, area-specific files, plus the repo-root AGENTS.md, the open and portable convention for agent instructions.

Because they are files in git, they get the same lifecycle as any other source: code review, blame, PR history, rollback. Standards become an artifact instead of tribal knowledge in someone's head or a buried Slack thread.