diff --git a/deploy/deploy.yaml b/deploy/deploy.yaml
index e63399c5..309101bf 100644
--- a/deploy/deploy.yaml
+++ b/deploy/deploy.yaml
@@ -95,4 +95,6 @@ steps:
 artifacts:
   objects:
     location: 'gs://$PROJECT_ID/screentest-artifacts'
-    paths: ['tests/screentest/output/**']
+    paths:
+      - 'tests/screentest/output/*'
+      - 'tests/screentest/output/testcases/*'
diff --git a/deploy/screentest.sh b/deploy/screentest.sh
index 47421e82..fd003d0b 100755
--- a/deploy/screentest.sh
+++ b/deploy/screentest.sh
@@ -10,23 +10,48 @@ source private/devtools/lib.sh || { echo "Are you at repo root?"; exit 1; }
 usage() {
   >&2 cat <<EOUSAGE
 
-  Usage: $0 [exp|dev|staging|prod|beta] IDTOKEN
+  Usage: $0 [OPTIONS] [exp|dev|staging|prod|beta] [IDTOKEN]
 
   Run the screentest check against a live instance of the given environment.
   These tests will only pass against staging and prod.
+  If IDTOKEN is omitted, it is read from the file _ID_TOKEN.
+
+  Options:
+    -neverfail
+      Do not return a non-zero exit code, even if the screentests fail.
+      This causes Cloud Build to upload screentest results for debugging.
+      It should never be used as part of a normal deployment.
 
 EOUSAGE
   exit 1
 }
 
 main() {
+  if [[ $# = 0 ]]; then
+    usage
+  fi
+  neverfail=false
+  if [[ $1 = -neverfail ]]; then
+    neverfail=true
+    shift
+  fi
+
   local env=$1
   local idtoken=$2
   check_env $env
   if [ -z $idtoken ]; then
     idtoken=$(cat _ID_TOKEN)
   fi
-  ./tests/screentest/run.sh -idtoken $idtoken -concurrency 1 $env
+  ./tests/screentest/run.sh -idtoken $idtoken -concurrency 1 $env || $neverfail
+  # If the tests passed, the tests/screentest/output directory will be empty.
+  # That causes the "artifacts" part of deploy.yaml to fail, because Cloud Build
+  # can't find any files there to upload. So create something there.
+  outdir=tests/screentest/output
+  if [[ ! -d $outdir ]]; then
+    mkdir -p $outdir/testcases
+    touch $outdir/success
+    touch $outdir/testcases/success
+  fi
 }
 
 main $@