diff --git a/system/machines/server/modules/nginx/default.nix b/system/machines/server/modules/nginx/default.nix
index 8b3b97d..33427e7 100644
--- a/system/machines/server/modules/nginx/default.nix
+++ b/system/machines/server/modules/nginx/default.nix
@@ -78,6 +78,14 @@ in
       recommendedGzipSettings = true;
       eventsConfig = "worker_connections 4096;";
 
+      # CORS origin allowlist for MCP servers
+      commonHttpConfig = ''
+        map $http_origin $mcp_cors_origin {
+          default "";
+          "https://ai.${domain}" "https://ai.${domain}";
+        }
+      '';
+
       # Catch-all default - friendly error for unknown subdomains
       virtualHosts."_" = {
         default = true;
@@ -148,6 +156,23 @@ in
           proxyWebsockets = true;
           extraConfig = ''
             include ${config.sops.templates."nginx-mcp-auth.conf".path};
+
+            # CORS — $mcp_cors_origin is set by the http-level map
+            # and is empty for disallowed origins
+            if ($request_method = OPTIONS) {
+              add_header Access-Control-Allow-Origin $mcp_cors_origin always;
+              add_header Access-Control-Allow-Methods "GET, POST, OPTIONS" always;
+              add_header Access-Control-Allow-Headers "Content-Type, Authorization, X-API-Key" always;
+              add_header Access-Control-Allow-Credentials "true" always;
+              add_header Access-Control-Max-Age 86400 always;
+              return 204;
+            }
+
+            add_header Access-Control-Allow-Origin $mcp_cors_origin always;
+            add_header Access-Control-Allow-Methods "GET, POST, OPTIONS" always;
+            add_header Access-Control-Allow-Headers "Content-Type, Authorization, X-API-Key" always;
+            add_header Access-Control-Allow-Credentials "true" always;
+
             proxy_read_timeout 300s;
             proxy_send_timeout 300s;
           '';
diff --git a/system/machines/server/system.nix b/system/machines/server/system.nix
index 43b75f6..1ceac33 100644
--- a/system/machines/server/system.nix
+++ b/system/machines/server/system.nix
@@ -40,7 +40,7 @@
     nginx = {
       enable = true;
     };
-    sandpack.enable = true;
+    sandpack.enable = false;
     forgejo.enable = true;
     frigate.enable = true;
     immich.enable = true;