diff --git a/ci-scripts/report-size.sh b/ci-scripts/report-size.sh
index d85cdbb..242f5de 100755
--- a/ci-scripts/report-size.sh
+++ b/ci-scripts/report-size.sh
@@ -1,7 +1,10 @@
 #!/bin/sh
 
+set -eu
+
 package_size_table() {
 	packages=$(nix flake show --json 2>/dev/null | jq --raw-output '.packages."x86_64-linux" | ".#" + keys[]')
+	echo 'Building packages' >&2
 	# we want to split the words as each of them is a different installable
 	# shellcheck disable=SC2086
 	nix build $packages
@@ -17,7 +20,7 @@ package_size_table() {
 	EOF
 }
 
-if [ "$CI" = "true" ]; then
+if [ "${CI-false}" = "true" ]; then
 	pr_number=$(curl -X 'GET' \
 		"$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/pulls?state=open&sort=recentupdate" \
 		-H 'accept: application/json' |
@@ -42,8 +45,9 @@ if [ "$CI" = "true" ]; then
 	data=$(echo '{}' | jq --arg comment "$comment" '.body=$comment')
 	echo "$data"
 	curl -o - -v -X 'POST' \
-		"$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/issues/$pr_number/comments?token=$GITHUB_TOKEN" \
+		"$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/issues/$pr_number/comments" \
 		-H 'accept: application/json' \
+		-H "Authorization: token $GITHUB_TOKEN" \
 		-H 'Content-Type: application/json' \
 		-d "$data"
 else