diff --git a/demos/use_cases/preference_based_routing/arch_config.yaml b/demos/use_cases/preference_based_routing/arch_config.yaml
index 75a43d77..a8cd5bb8 100644
--- a/demos/use_cases/preference_based_routing/arch_config.yaml
+++ b/demos/use_cases/preference_based_routing/arch_config.yaml
@@ -13,7 +13,7 @@ listeners:
 llm_providers:
 
   - name: arch-router
-    access_key: $ARCH_API_KEY
+    access_key: ${ARCH_API_KEY:-none}
     provider_interface: arch
     model: Arch-Router
 
diff --git a/demos/use_cases/preference_based_routing/arch_config_local.yaml b/demos/use_cases/preference_based_routing/arch_config_local.yaml
index 607d180a..5edef428 100644
--- a/demos/use_cases/preference_based_routing/arch_config_local.yaml
+++ b/demos/use_cases/preference_based_routing/arch_config_local.yaml
@@ -13,7 +13,7 @@ listeners:
 llm_providers:
 
   - name: arch-router
-    access_key: $ARCH_API_KEY
+    access_key: ${ARCH_API_KEY:-none}
     provider_interface: arch
     model: hf.co/katanemo/Arch-Router-1.5B.gguf:Q4_K_M
     endpoint: host.docker.internal:11434