diff --git a/.agents/scripts/launch.sh b/.agents/scripts/launch.sh
index bf51c11..61612da 100755
--- a/.agents/scripts/launch.sh
+++ b/.agents/scripts/launch.sh
@@ -56,9 +56,10 @@ else
   git worktree add "$dir" -b "$branch" "$base"
 fi
 
-# npm ci only once task 01 has produced a package.json. Before that there is no
-# toolchain to install, and no hooks to verify.
-if [ -f "$dir/package.json" ]; then
+# npm ci only once task 01 has produced a lockfile. The pre-existing root
+# package.json carries two scripts and no dependencies, so before task 01 there
+# is no toolchain to install and no hooks to verify.
+if [ -f "$dir/package-lock.json" ]; then
   ( cd "$dir" && npm ci --prefer-offline && .agents/scripts/verify-hooks.sh )
 fi