diff --git a/AGENTS.md b/AGENTS.md
index 89a1e5a6..b077cdc2 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -15,6 +15,9 @@ Design docs are maintained in Obsidian Vault: `\\Truenas\smb\Obsidian Vault\Colo
 
 - Always use the shared Obsidian Vault at `\\Truenas\smb\Obsidian Vault\Colosseum` for project documentation updates.
 - Do not write Colosseum design notes to `C:\Users\dal4s\OneDrive\문서\Obsidian Vault\Colosseum`; that path is not the active vault for this project.
+- When editing user-authored Obsidian notes, preserve the user's original text structure as much as possible.
+- If Codex adds interpretation, clarification, proposals, or implementation notes to a user-authored note, put them in a clearly labeled separate section such as `Codex 보완 메모` or `Codex 제안` so the added content is visibly distinguishable from the user's original writing.
+- Avoid silently rewriting or blending Codex-authored guidance into the user's original bullet lists unless the user explicitly asks for a rewrite.
 
 ### Game Concept
 - **Genre**: Online multiplayer co-op action RPG (3rd person)