diff --git a/Framework/KubernetesWorkflow/ContainerRecipe.cs b/Framework/KubernetesWorkflow/ContainerRecipe.cs
index 772ff20..6bac0ff 100644
--- a/Framework/KubernetesWorkflow/ContainerRecipe.cs
+++ b/Framework/KubernetesWorkflow/ContainerRecipe.cs
@@ -24,6 +24,8 @@
             {
                 Name = $"ctnr{Number}";
             }
+
+            if (exposedPorts.Any(p => string.IsNullOrEmpty(p.Tag))) throw new Exception("Port tags are required for all exposed ports.");
         }
 
         public string Name { get; }
diff --git a/Framework/KubernetesWorkflow/ContainerRecipeFactory.cs b/Framework/KubernetesWorkflow/ContainerRecipeFactory.cs
index 8d19398..6e50a1b 100644
--- a/Framework/KubernetesWorkflow/ContainerRecipeFactory.cs
+++ b/Framework/KubernetesWorkflow/ContainerRecipeFactory.cs
@@ -50,12 +50,12 @@ namespace KubernetesWorkflow
         protected int Index { get; private set; } = 0;
         protected abstract void Initialize(StartupConfig config);
 
-        protected Port AddExposedPort(string tag = "")
+        protected Port AddExposedPort(string tag)
         {
             return AddExposedPort(factory.CreatePort(tag));
         }
 
-        protected Port AddExposedPort(int number, string tag = "")
+        protected Port AddExposedPort(int number, string tag)
         {
             return AddExposedPort(factory.CreatePort(number, tag));
         }
@@ -67,7 +67,7 @@ namespace KubernetesWorkflow
             return p;
         }
 
-        protected void AddExposedPortAndVar(string name, string tag = "")
+        protected void AddExposedPortAndVar(string name, string tag)
         {
             AddEnvVar(name, AddExposedPort(tag));
         }
diff --git a/ProjectPlugins/CodexPlugin/CodexContainerRecipe.cs b/ProjectPlugins/CodexPlugin/CodexContainerRecipe.cs
index 905041a..867b9bf 100644
--- a/ProjectPlugins/CodexPlugin/CodexContainerRecipe.cs
+++ b/ProjectPlugins/CodexPlugin/CodexContainerRecipe.cs
@@ -8,8 +8,10 @@ namespace CodexPlugin
         private readonly MarketplaceStarter marketplaceStarter = new MarketplaceStarter();
 
         private const string DefaultDockerImage = "codexstorage/nim-codex:latest-dist-tests";
-        public const string MetricsPortTag = "metrics_port";
-        public const string DiscoveryPortTag = "discovery-port";
+        public const string ApiPortTag = "codex_api_port";
+        public const string ListenPortTag = "codex_listen_port";
+        public const string MetricsPortTag = "codex_metrics_port";
+        public const string DiscoveryPortTag = "codex_discovery_port";
 
         // Used by tests for time-constraint assertions.
         public static readonly TimeSpan MaxUploadTimePerMegabyte = TimeSpan.FromSeconds(2.0);
@@ -27,7 +29,7 @@ namespace CodexPlugin
 
             var config = startupConfig.Get<CodexStartupConfig>();
 
-            AddExposedPortAndVar("CODEX_API_PORT");
+            AddExposedPortAndVar("CODEX_API_PORT", ApiPortTag);
             AddEnvVar("CODEX_API_BINDADDR", "0.0.0.0");
 
             var dataDir = $"datadir{ContainerNumber}";
@@ -40,7 +42,7 @@ namespace CodexPlugin
             // This makes the node announce itself to its local (pod) IP address.
             AddEnvVar("NAT_IP_AUTO", "true");
 
-            var listenPort = AddExposedPort();
+            var listenPort = AddExposedPort(ListenPortTag);
             AddEnvVar("CODEX_LISTEN_ADDRS", $"/ip4/0.0.0.0/tcp/{listenPort.Number}");
 
             if (!string.IsNullOrEmpty(config.BootstrapSpr))
diff --git a/ProjectPlugins/MetricsPlugin/PrometheusContainerRecipe.cs b/ProjectPlugins/MetricsPlugin/PrometheusContainerRecipe.cs
index 26b9b48..2696915 100644
--- a/ProjectPlugins/MetricsPlugin/PrometheusContainerRecipe.cs
+++ b/ProjectPlugins/MetricsPlugin/PrometheusContainerRecipe.cs
@@ -7,11 +7,13 @@ namespace MetricsPlugin
         public override string AppName => "prometheus";
         public override string Image => "codexstorage/dist-tests-prometheus:latest";
 
+        public const string PortTag = "prometheus_port_tag";
+
         protected override void Initialize(StartupConfig startupConfig)
         {
             var config = startupConfig.Get<PrometheusStartupConfig>();
 
-            AddExposedPortAndVar("PROM_PORT");
+            AddExposedPortAndVar("PROM_PORT", PortTag);
             AddEnvVar("PROM_CONFIG", config.PrometheusConfigBase64);
         }
     }