diff --git a/.github/workflows/phylogenetic.yaml b/.github/workflows/phylogenetic.yaml
index 857b021..04901b7 100644
--- a/.github/workflows/phylogenetic.yaml
+++ b/.github/workflows/phylogenetic.yaml
@@ -55,22 +55,21 @@ jobs:
           METADATA_URL: ${{ inputs.metadata_url }}
         run: |
           config=""
-          if [[ "$TRIAL_NAME" || "$SEQUENCES_URL" || "$METADATA_URL" ]]; then
 
-            config+="--config"
-
-            if [[ "$TRIAL_NAME" ]]; then
-              config+=" deploy_url='s3://nextstrain-staging/zika_trials_"$TRIAL_NAME"_'"
-            fi
+          if [[ "$TRIAL_NAME" ]]; then
+            config+=" deploy_url='s3://nextstrain-staging/zika_trials_"$TRIAL_NAME"_'"
+          fi
 
-            if [[ "$SEQUENCES_URL" ]]; then
-              config+=" sequences_url='"$SEQUENCES_URL"'"
-            fi
+          if [[ "$SEQUENCES_URL" ]]; then
+            config+=" sequences_url='"$SEQUENCES_URL"'"
+          fi
 
-            if [[ "$METADATA_URL" ]]; then
-              config+=" metadata_url='"$METADATA_URL"'"
-            fi
+          if [[ "$METADATA_URL" ]]; then
+            config+=" metadata_url='"$METADATA_URL"'"
+          fi
 
+          if [[ $config ]]; then
+            config="--config $config"
           fi
 
           echo "config=$config" >> "$GITHUB_OUTPUT"