Rules and instruction files in every AI coding agent: .cursor/rules, CLAUDE.md, AGENTS.md, GEMINI.md, Copilot instructions and more (2026)

• Cursor: project rules are .mdc files in .cursor/rules (a plain .md file there is ignored). User Rules live in Customize, then Rules. Team Rules come from the dashboard on Team and Enterprise plans. AGENTS.md works in the root and in subfolders.
• Claude Code: ./CLAUDE.md or ./.claude/CLAUDE.md for the team, ~/.claude/CLAUDE.md for you, ./CLAUDE.local.md for private project notes. Run /init to generate one.
• OpenAI Codex: AGENTS.md in ~/.codex for global habits, then one AGENTS.md (or AGENTS.override.md) per directory from the repo root down to where you work.
• Gemini CLI: ~/.gemini/GEMINI.md globally and GEMINI.md in your project. /memory show prints what is loaded.
• GitHub Copilot: .github/copilot-instructions.md for the whole repo, .github/instructions/NAME.instructions.md with an applyTo glob for some files, and AGENTS.md anywhere in the repo.
• Cline: markdown files in .clinerules/ or .cline/rules/ in the project, and ~/Documents/Cline/Rules for global rules.
• Kiro: markdown steering files in .kiro/steering/ (workspace) or ~/.kiro/steering/ (global), plus AGENTS.md.
• Junie: .junie/AGENTS.md, then a root AGENTS.md, then the legacy .junie/guidelines.md. Global guidelines go in ~/.junie/AGENTS.md.
• Amp: AGENTS.md in the working directory and its parents, plus ~/.config/amp/AGENTS.md.
• goose: AGENTS.md and .goosehints, globally in ~/.config/goose/.goosehints or per project.
• Zed: ~/.config/zed/AGENTS.md for you, then the first project file it finds from a list that starts with .rules, .cursorrules and .windsurfrules and includes AGENTS.md and CLAUDE.md.
• Aider: no special file. Write CONVENTIONS.md and load it with aider --read CONVENTIONS.md or read: in .aider.conf.yml.

Almost. These agents read AGENTS.md with no extra setup: Cursor, Codex, GitHub Copilot, Cline, Kiro, Junie, Amp, goose and Zed. Claude Code reads AGENTS.md only when the repo has no CLAUDE.md. If you keep both, add @AGENTS.md inside CLAUDE.md so Claude Code imports it. Gemini CLI needs context.fileName in settings.json.

@AGENTS.md

## Claude Code only
- Use plan mode for changes that touch more than three files.

{
  "context": {
    "fileName": ["AGENTS.md", "GEMINI.md"]
  }
}

Cursor's current rules documentation describes .cursor/rules .mdc files, User Rules, Team Rules and AGENTS.md. It does not document a root .cursorrules file. Other tools still read that file name: Cline detects .cursorrules automatically, and Zed checks .cursorrules second in its list of project instruction files. For new projects, put shared instructions in AGENTS.md and Cursor-specific scoping in .cursor/rules.

• Cursor: globs in the .mdc frontmatter, with alwaysApply: false.
• Claude Code: a paths field in a markdown file under .claude/rules/.
• GitHub Copilot: applyTo in the frontmatter of an .instructions.md file.
• Cline: a paths list in YAML frontmatter.
• Kiro: inclusion: fileMatch with a fileMatchPattern.
• Amp: globs in the front matter of a file you @-mention from AGENTS.md.
• Codex: put an AGENTS.md or AGENTS.override.md in the subfolder that needs different rules.

---
globs: src/components/**/*.tsx
alwaysApply: false
---

- Use named exports, not default exports

---
applyTo: "**/*.py"
---

Use type hints on every public function.

• Cursor rules setup: .mdc frontmatter, Team Rules and AGENTS.md
• Claude Code CLAUDE.md: locations, imports and AGENTS.md
• Codex AGENTS.md: global, project and override files
• Gemini CLI GEMINI.md: locations, imports and /memory
• GitHub Copilot custom instructions
• Cline Rules: workspace, global and conditional rules
• Kiro steering files and inclusion modes
• Junie guidelines and AGENTS.md
• Amp AGENTS.md and glob-scoped guidance
• goose .goosehints and AGENTS.md
• Zed instruction files, MCP and tool permissions
• Aider CONVENTIONS.md and .aider.conf.yml
• Copy-paste Cursor rule templates
• AGENTS.md reference and generator