diff --git a/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandDescriptor.kt b/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandDescriptor.kt
index ac509ed74..a5866c826 100644
--- a/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandDescriptor.kt
+++ b/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandDescriptor.kt
@@ -68,7 +68,7 @@ class CommandDescriptor(
     /**
      * `fullName + aliases`
      */
-    val allNames = arrayOf(fullName, *aliases)
+    val allNames: Array<CommandFullName> = arrayOf(fullName, *aliases)
 
     override fun equals(other: Any?): Boolean {
         if (this === other) return true
@@ -117,7 +117,7 @@ internal fun Any.flattenCommandComponents(): Sequence<Any> = when (this) {
     is String -> splitToSequence(' ').filterNot { it.isBlank() }
     is PlainText -> content.flattenCommandComponents()
     is SingleMessage -> sequenceOf(this)
-    is MessageChain -> this.asSequence().map { it.flattenCommandComponents() }
+    is MessageChain -> this.asSequence().flatMap { it.flattenCommandComponents() }
     else -> throw IllegalArgumentException("Illegal component: $this")
 }
 
@@ -134,11 +134,14 @@ internal fun CommandFullName.checkFullName(errorHint: String): CommandFullName {
 inline fun CommandDescriptor(
     vararg fullName: Any,
     block: CommandDescriptorBuilder.() -> Unit = {}
-): CommandDescriptor = CommandDescriptorBuilder(fullName).apply(block).build()
+): CommandDescriptor = CommandDescriptorBuilder(*fullName).apply(block).build()
 
 class CommandDescriptorBuilder(
-    vararg val fullName: Any
+    vararg fullName: Any
 ) {
+    @PublishedApi
+    internal var fullName: CommandFullName = fullName.checkFullName("fullName")
+
     @PublishedApi
     internal var context: CommandParserContext = CommandParserContext.Builtins
 
diff --git a/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandManager.kt b/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandManager.kt
index 915307de3..19a64f127 100644
--- a/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandManager.kt
+++ b/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandManager.kt
@@ -25,16 +25,14 @@ fun CommandOwner.unregisterAllCommands() {
  * 注册一个指令. 若此指令已经注册或有已经注册的指令与 [allNames] 重名, 返回 `false`
  */
 fun Command.register(): Boolean = InternalCommandManager.modifyLock.withLock {
-    with(descriptor) {
-        if (findDuplicate() != null) {
-            return false
-        }
-        InternalCommandManager.registeredCommands.add(this@register)
-        for (name in this.allNames) {
-            InternalCommandManager.nameToCommandMap[name] = this@register
-        }
-        return true
+    if (findDuplicate() != null) {
+        return false
     }
+    InternalCommandManager.registeredCommands.add(this@register)
+    for (name in this.allNames) {
+        InternalCommandManager.nameToCommandMap[name] = this@register
+    }
+    return true
 }
 
 /**
@@ -85,8 +83,7 @@ suspend fun CommandSender.execute(command: Command, args: CommandArgs): Boolean
 }
 
 suspend fun Command.execute(sender: CommandSender, args: CommandArgs): Boolean = sender.execute(this, args)
-suspend fun Command.execute(sender: CommandSender, vararg args: Any): Boolean = sender.execute(this, args)
-suspend fun CommandSender.execute(command: Command, vararg args: Any): Boolean = command.execute(this, args)
+suspend fun CommandSender.execute(vararg args: Any): Boolean = args.toList().executeCommand(this)
 
 
 internal suspend fun List<Any>.executeCommand(sender: CommandSender): Boolean {
diff --git a/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/DefaultCommands.kt b/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/DefaultCommands.kt
index 09198e400..ad9be438e 100644
--- a/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/DefaultCommands.kt
+++ b/backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/DefaultCommands.kt
@@ -10,24 +10,14 @@
 package net.mamoe.mirai.console.command
 
 suspend fun main() {
-    ConsoleCommandSender.execute(DefaultCommands.Test, "test")
-}
 
-internal object DefaultCommands {
-    
-    object Test : ConsoleCommand(
-        CommandDescriptor("test") {
-            param<String>()
-        }
-    ) {
-        override suspend fun onCommand(sender: CommandSender, args: CommandArgs): Boolean {
-            val s = args.getReified<String>()
-            sender.sendMessage(s)
-            return true
-        }
+    if (ConsoleCommandSender.execute("test")) {
+
     }
 }
 
+internal object DefaultCommands
+
 /*
 
 /**
diff --git a/backend/mirai-console/src/test/java/net/mamoe/mirai/console/command/TestCommands.kt b/backend/mirai-console/src/test/java/net/mamoe/mirai/console/command/TestCommands.kt
new file mode 100644
index 000000000..fdd46931c
--- /dev/null
+++ b/backend/mirai-console/src/test/java/net/mamoe/mirai/console/command/TestCommands.kt
@@ -0,0 +1,75 @@
+/*
+ * Copyright 2020 Mamoe Technologies and contributors.
+ *
+ * 此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
+ * Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.
+ *
+ * https://github.com/mamoe/mirai/blob/master/LICENSE
+ */
+
+@file:Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
+
+package net.mamoe.mirai.console.command
+
+import net.mamoe.mirai.console.plugins.PluginBase
+import net.mamoe.mirai.message.data.PlainText
+import net.mamoe.mirai.message.data.messageChainOf
+import net.mamoe.mirai.message.data.toMessage
+import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+
+val plugin: PluginBase = object : PluginBase() {
+
+}
+
+internal object TestCommand : PluginCommand(
+    plugin,
+    CommandDescriptor("test") {
+        param<String>()
+    }
+) {
+    override suspend fun onCommand(sender: CommandSender, args: CommandArgs): Boolean {
+        val s = args.getReified<String>()
+        sender.sendMessage(s)
+        return true
+    }
+}
+
+internal class TestCommands {
+    @Test
+    fun testFlatten() {
+        assertEquals(listOf("test", "v1"), "test v1".flattenCommandComponents().toList())
+        assertEquals(listOf("test", "v1"), PlainText("test v1").flattenCommandComponents().toList())
+        assertEquals(listOf("test", "v1"), arrayOf("test ", "v1", "   ").flattenCommandComponents().toList())
+        assertEquals(
+            listOf("test", "v1"),
+            messageChainOf("test v1".toMessage(), " ".toMessage()).flattenCommandComponents().toList()
+        )
+    }
+
+    @Test
+    fun testRegister() {
+        assertTrue(TestCommand.register())
+        assertEquals(listOf("test"), TestCommand.allNames.single().toList())
+
+        assertFalse(TestCommand.register())
+        assertFalse(
+            object : PluginCommand(
+                plugin,
+                CommandDescriptor("test") {
+                    param<String>()
+                }
+            ) {
+                override suspend fun onCommand(sender: CommandSender, args: CommandArgs): Boolean {
+                    val s = args.getReified<String>()
+                    sender.sendMessage(s)
+                    return true
+                }
+            }.register()
+        )
+    }
+}
+