diff --git a/agents/git-ops.md b/agents/git-ops.md
index ab529e1a..e564c222 100644
--- a/agents/git-ops.md
+++ b/agents/git-ops.md
@@ -121,6 +121,16 @@ Good callers will provide semantic context in their delegation message. Use ever
 - Check authorship before amending
 - Quote paths with spaces
 
+## Idempotency Discipline
+
+Disk and repo state are the source of truth — not your memory of what you already ran.
+
+**Before ANY clone:** check whether the target directory already exists with the right remote (`git -C <dir> remote get-url origin`). If it matches, `git -C <dir> fetch` instead of re-cloning. Never clone the same URL twice in one session.
+
+**Remote-discovery commands run at most once per remote per session.** `git ls-remote`, default-branch lookups, and similar discovery calls are one-shot — write the result into your working notes immediately and reuse it. Don't re-derive it.
+
+**About to repeat a command you believe you already ran? Stop.** Check the filesystem/repo state first. Repeated identical commands are the signature of lost context, not a reason to run them again.
+
 ## Common Git Commands
 
 ### Status & Information