Egor Urvanov

Agent rules

Harness · rules

Short do and do-not instructions the harness loads into the agent context: always, or only when the agent touches matching files. It is a common concept: in Claude Code rules live in CLAUDE.md and the .claude/rules folder, in Cursor in .cursor/rules, in Codex in AGENTS.md. The agent treats a rule as advice; a no-exceptions prohibition is enforced with a hook.

ruleruleruleagentproject biblehow and whyalways"tests: npm test"by file masksrc/api/**on agent request"how to write migrations"derivedgo into contexta rule is advice, a ban is a hook● model, people, systems, data  ● agent and harnessShort instructions for the agent: always, or when it touches matching files

Rules and the project bible

RulesProject bible
Answershow to act herehow the project is built and why
Formshort do and do-not instructionsa connected description and principles
When the agent reads italways or when it touches matching filesbefore work, as a whole
Example"run tests with npm test""payments are a separate system we do not edit"
Where it comes fromderived from the bible and agent mistakeswritten by people who know the project

Source: Cursor Rules docs

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