diff --git a/src/main/kotlin/net/minecrell/pluginyml/bukkit/BukkitPlugin.kt b/src/main/kotlin/net/minecrell/pluginyml/bukkit/BukkitPlugin.kt
index b8b20f2..5e1f09c 100644
--- a/src/main/kotlin/net/minecrell/pluginyml/bukkit/BukkitPlugin.kt
+++ b/src/main/kotlin/net/minecrell/pluginyml/bukkit/BukkitPlugin.kt
@@ -53,6 +53,13 @@ class BukkitPlugin : PlatformPlugin<BukkitPluginDescription>("Bukkit", "plugin.y
         val main = description.main ?: throw InvalidPluginDescriptionException("Main class is not defined")
         if (main.isEmpty()) throw InvalidPluginDescriptionException("Main class cannot be empty")
         if (main.startsWith("org.bukkit.")) throw InvalidPluginDescriptionException("Main may not be within the org.bukkit namespace")
+
+        for (command in description.commands) {
+            if (command.name.contains(':')) throw InvalidPluginDescriptionException("Command '${command.name}' cannot contain ':'")
+            command.aliases?.forEach { alias ->
+                if (alias.contains(':')) throw InvalidPluginDescriptionException("Alias '$alias' of '${command.name}' cannot contain ':'")
+            }
+        }
     }
 
 }
diff --git a/src/main/kotlin/net/minecrell/pluginyml/nukkit/NukkitPlugin.kt b/src/main/kotlin/net/minecrell/pluginyml/nukkit/NukkitPlugin.kt
index b3df076..dcb435c 100644
--- a/src/main/kotlin/net/minecrell/pluginyml/nukkit/NukkitPlugin.kt
+++ b/src/main/kotlin/net/minecrell/pluginyml/nukkit/NukkitPlugin.kt
@@ -48,6 +48,13 @@ class NukkitPlugin : PlatformPlugin<NukkitPluginDescription>("Nukkit", "nukkit.y
         if (main.startsWith("cn.nukkit.")) throw InvalidPluginDescriptionException("Main class cannot be within cn.nukkit. package")
 
         if (description.api?.isEmpty() != false) throw InvalidPluginDescriptionException("Nukkit API version is not set")
+
+        for (command in description.commands) {
+            if (command.name.contains(':')) throw InvalidPluginDescriptionException("Command '${command.name}' cannot contain ':'")
+            command.aliases?.forEach { alias ->
+                if (alias.contains(':')) throw InvalidPluginDescriptionException("Alias '$alias' of '${command.name}' cannot contain ':'")
+            }
+        }
     }
 
 }