What problem does it solve? Maintaining AI coding-agent rule files that work consistently across Claude Code, GitHub Copilot, Cursor, and OpenAI Codex is error-prone because each tool reads rules from different paths and uses different frontmatter fields. This Skill enforces a single convention so every rule file stays compatible with all four tools. ## Core Features & Use Cases - Cross-tool frontmatter authoring: Generates the correct description, globs, paths, applyTo, and alwaysApply fields so one rule file scopes properly in every supported tool. - Directory and category conventions: Decides whether a rule belongs flat in .agents/rules/ or in a category subfolder (created when 2+ rules share a topic), and keeps the symlink chain (.agents/rules → .github/instructions/) intact. - On-demand context injection: Ships a scripts/inject-context.sh hook script that injects the convention into the session once per prompt, deduped by session id. - Use Case: When you ask an agent to add a new backend logging rule, it creates .agents/rules/backend/logging.instructions.md with mirrored scope patterns, a changelog entry, and updated cross-references. ## Quick Start Ask the agent to create a new rule file for backend API standards in .agents/rules/ with frontmatter that works across Claude Code, Copilot, Cursor, and Codex.