diff --git a/plugins/upsun/.mcp.json b/plugins/upsun/.mcp.json
index 455e5bc..52b71e3 100644
--- a/plugins/upsun/.mcp.json
+++ b/plugins/upsun/.mcp.json
@@ -4,7 +4,7 @@
       "type": "http",
       "url": "https://mcp.upsun.com/mcp",
       "headers": {
-        "upsun-api-token": "${UPSUN_API_TOKEN}",
+        "upsun-api-token": "${UPSUN_API_TOKEN:-}",
         "enable-write": "false"
       }
     }