diff --git a/AGENTS.md b/AGENTS.md
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+# AGENTS.md
+
+## Worktree Safety
+
+Always use the primary working directory (the worktree) for all file reads and edits. Never follow absolute paths from subagent results that point to the main repo.
diff --git a/CLAUDE.md b/CLAUDE.md
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 # CLAUDE.md
 
+See also: [AGENTS.md](./AGENTS.md) for agent-specific rules.
+
 ## Package Manager
 
 This project uses **pnpm**. Never use `npm` or `yarn`.