diff --git a/contrib/checkdiff.bash b/contrib/checkdiff.bash
index 57cf8e99..cfcef13d 100755
--- a/contrib/checkdiff.bash
+++ b/contrib/checkdiff.bash
@@ -13,7 +13,7 @@ edited () {
 
 dependency () {
 	if edited "$1" && ! edited "$2"; then
-		echo "'$1' was modified, but not '$2'! $3" | xargs
+		echo >&2 "::warning '$1' was modified, but not '$2'! $3" | xargs
 	fi
 }
 
diff --git a/test/asm/test.sh b/test/asm/test.sh
index 6d75e958..f1c89f51 100755
--- a/test/asm/test.sh
+++ b/test/asm/test.sh
@@ -169,7 +169,7 @@ done
 if [[ "$failed" -eq 0 ]]; then
 	echo "${bold}${green}All ${tests} tests passed!${rescolors}${resbold}"
 else
-	echo "${bold}${red}${failed} of the tests failed!${rescolors}${resbold}"
+	echo "::warning ${bold}${red}${failed} of the RGBASM tests failed!${rescolors}${resbold}"
 fi
 
 exit $rc
diff --git a/test/fix/test.sh b/test/fix/test.sh
index 360ef758..e9fc4491 100755
--- a/test/fix/test.sh
+++ b/test/fix/test.sh
@@ -125,7 +125,7 @@ rc=$((rc || $?))
 if [[ "$failed" -eq 0 ]]; then
 	echo "${bold}${green}All ${tests} tests passed!${rescolors}${resbold}"
 else
-	echo "${bold}${red}${failed} of the tests failed!${rescolors}${resbold}"
+	echo "::warning ${bold}${red}${failed} of the RGBFIX tests failed!${rescolors}${resbold}"
 fi
 
 exit $rc
diff --git a/test/gfx/test.sh b/test/gfx/test.sh
index 8de74318..c3a44f0c 100755
--- a/test/gfx/test.sh
+++ b/test/gfx/test.sh
@@ -104,7 +104,7 @@ done
 if [[ "$failed" -eq 0 ]]; then
 	echo "${bold}${green}All ${tests} tests passed!${rescolors}${resbold}"
 else
-	echo "${bold}${red}${failed} of the tests failed!${rescolors}${resbold}"
+	echo "::warning ${bold}${red}${failed} of the RGBGFX tests failed!${rescolors}${resbold}"
 fi
 
 exit $rc
diff --git a/test/link/test.sh b/test/link/test.sh
index c66343f4..a6615c8b 100755
--- a/test/link/test.sh
+++ b/test/link/test.sh
@@ -331,7 +331,7 @@ evaluateTest
 if [[ "$failed" -eq 0 ]]; then
 	echo "${bold}${green}All ${tests} tests passed!${rescolors}${resbold}"
 else
-	echo "${bold}${red}${failed} of the tests failed!${rescolors}${resbold}"
+	echo "::warning ${bold}${red}${failed} of the RGBLINK tests failed!${rescolors}${resbold}"
 fi
 
 exit $rc
diff --git a/test/run-tests.sh b/test/run-tests.sh
index d8985ed8..bd31494b 100755
--- a/test/run-tests.sh
+++ b/test/run-tests.sh
@@ -63,7 +63,7 @@ test_downstream() { # owner repo make-target build-file build-hash
 	make -j4 "$3" RGBDS=../../
 	hash="$(sha1sum -b "$4" | head -c 40)"
 	if [ "$hash" != "$5" ]; then
-		echo >&2 'SHA-1 hash of '"$4"' did not match: '"$hash"
+		echo >&2 '::warning SHA-1 hash of '"$4"' did not match: '"$hash"
 		return 1
 	fi
 	popd