yg init integrates with your AI tool by creating or updating the right instruction file — so the agent knows how to work with Yggdrasil.

Platform	File created/updated by yg init	Touches user files?
Cursor	.cursor/rules/yggdrasil.mdc	❌ No
Claude Code	CLAUDE.md (single @... line)	⚠️ Minimal (1 line)
GitHub Copilot	.github/copilot-instructions.md (append section)	⚠️ Appends a section
Cline	.clinerules/yggdrasil.md	❌ No
RooCode	.roo/rules/yggdrasil.md	❌ No
Codex	AGENTS.md (append section)	⚠️ Appends a section
Windsurf	.windsurf/rules/yggdrasil.md	❌ No
Aider	.aider.conf.yml (adds read: entry)	⚠️ Minimal (1 line)
Gemini CLI	GEMINI.md (single @... line)	⚠️ Minimal (1 line)
Amp	AGENTS.md (single @... line)	⚠️ Minimal (1 line)
OpenCode	AGENTS.md (append section)	⚠️ Appends a section
CodeBuddy	.codebuddy/rules/yggdrasil/RULE.mdc	❌ No
Generic	.yggdrasil/agent-rules.md	❌ No

Notes:

• "No" — yg init creates a dedicated Yggdrasil file.
• "Minimal" — one line is added to an existing file.
• "Append section" — a clearly delimited section is added; no existing content is modified.
• Codex, Amp, and OpenCode all write to AGENTS.md using different formats. Do not initialize more than one of these platforms simultaneously.