diff --git a/.claude/skills/pr-review/SKILL.md b/.claude/skills/pr-review/SKILL.md
index 8a9241b63..1840c4850 100644
--- a/.claude/skills/pr-review/SKILL.md
+++ b/.claude/skills/pr-review/SKILL.md
@@ -16,15 +16,17 @@ on the branch type. All reviewers must approve for a clean review.
 
 ## Workflow
 
-### 0. Branch guard — MUST be on `main`
+### 0. Branch guard — MUST be run by a Claude instance in the `main` worktree
 
 ```bash
 git branch --show-current
 ```
 
 If the current branch is **not `main`**, stop immediately and tell the user:
-"PR reviews must be run from the `main` worktree. Switch to `main` first."
-Do NOT proceed with the review from a team branch.
+"PR reviews must be run by a Claude instance in the `main` worktree."
+Do NOT proceed with the review. Do NOT work around this by reading files
+from another worktree — the review agent itself must be running in main.
+Stop and wait for the user to invoke `/pr-review` from main.
 
 ### 1. Determine the branch to review