diff --git a/mirai-core-api/src/commonMain/kotlin/message/code/CodableMessage.kt b/mirai-core-api/src/commonMain/kotlin/message/code/CodableMessage.kt
index 223fb3659..9e42f8d2c 100644
--- a/mirai-core-api/src/commonMain/kotlin/message/code/CodableMessage.kt
+++ b/mirai-core-api/src/commonMain/kotlin/message/code/CodableMessage.kt
@@ -9,6 +9,7 @@
 
 package net.mamoe.mirai.message.code
 
+import net.mamoe.mirai.message.code.MiraiCode.parseMiraiCode
 import net.mamoe.mirai.message.data.*
 import net.mamoe.mirai.utils.MiraiExperimentalApi
 
@@ -16,7 +17,7 @@ import net.mamoe.mirai.utils.MiraiExperimentalApi
 /**
  * 可以使用 mirai 码表示的 [Message] 类型.
  *
- * 从字符串解析 mirai 码：[parseMiraiCode]
+ * 从字符串解析 mirai 码：[MiraiCode.parseMiraiCode]
  *
  * @see At
  * @see AtAll
@@ -25,6 +26,8 @@ import net.mamoe.mirai.utils.MiraiExperimentalApi
  * @see Image
  * @see FlashImage
  * @see PokeMessage
+ *
+ * @see MiraiCode
  */
 public interface CodableMessage : Message {
     /**
diff --git a/mirai-core-api/src/commonMain/kotlin/message/code/MiraiCode.kt b/mirai-core-api/src/commonMain/kotlin/message/code/MiraiCode.kt
index dda99fef8..d76eb0df5 100644
--- a/mirai-core-api/src/commonMain/kotlin/message/code/MiraiCode.kt
+++ b/mirai-core-api/src/commonMain/kotlin/message/code/MiraiCode.kt
@@ -7,8 +7,6 @@
  *  https://github.com/mamoe/mirai/blob/master/LICENSE
  */
 
-@file:JvmMultifileClass
-@file:JvmName("MiraiCode")
 @file:Suppress("unused")
 
 package net.mamoe.mirai.message.code
@@ -20,19 +18,49 @@ import net.mamoe.mirai.message.data.MessageChain
 import net.mamoe.mirai.utils.safeCast
 
 /**
- * 解析形如 "[mirai:]" 的 mirai 码, 即 [Message.toString] 返回的内容.
+ * Mirai 码相关操作.
  */
-@JvmOverloads
-public fun String.parseMiraiCode(contact: Contact? = null): MessageChain = parseMiraiCodeImpl(contact)
+public object MiraiCode {
+    /**
+     * 解析形如 "[mirai:]" 的 mirai 码, 即 [Message.toString] 返回的内容.
+     */
+    @JvmOverloads
+    @JvmStatic
+    public fun String.parseMiraiCode(contact: Contact? = null): MessageChain = parseMiraiCodeImpl(contact)
 
-public fun Iterable<Message>.toMiraiCode(): String = iterator().toMiraiCode()
-public fun Sequence<Message>.toMiraiCode(): String = iterator().toMiraiCode()
-public fun Array<out Message>.toMiraiCode(): String = iterator().toMiraiCode()
-public fun Iterator<Message>.toMiraiCode(): String = buildString {
-    this@toMiraiCode.forEach {
-        it.safeCast<CodableMessage>()?.appendMiraiCodeTo(this)
+    /**
+     * 转换得到 mirai 码.
+     */
+    @JvmStatic
+    public fun Iterable<Message>.toMiraiCode(): String = iterator().toMiraiCode()
+
+    /**
+     * 转换得到 mirai 码.
+     */
+    @JvmStatic
+    public fun Sequence<Message>.toMiraiCode(): String = iterator().toMiraiCode()
+
+    /**
+     * 转换得到 mirai 码.
+     */
+    @JvmStatic
+    public fun Array<out Message>.toMiraiCode(): String = iterator().toMiraiCode()
+
+    /**
+     * 转换得到 mirai 码.
+     */
+    @JvmStatic
+    public fun Iterator<Message>.toMiraiCode(): String = buildString {
+        this@toMiraiCode.forEach {
+            it.safeCast<CodableMessage>()?.appendMiraiCodeTo(this)
+        }
     }
-}
 
-@Suppress("EXTENSION_SHADOWED_BY_MEMBER")// for better Java API.
-public fun CodableMessage.toMiraiCode(): String = this.toMiraiCode() // member function
+    /**
+     * 转换得到 mirai 码.
+     * @see CodableMessage.toMiraiCode
+     */
+    @Suppress("EXTENSION_SHADOWED_BY_MEMBER")// for better Java API.
+    @JvmStatic
+    public fun CodableMessage.toMiraiCode(): String = this.toMiraiCode() // member function
+}
diff --git a/mirai-core-api/src/commonMain/kotlin/message/code/internal/impl.kt b/mirai-core-api/src/commonMain/kotlin/message/code/internal/impl.kt
index d85efa46c..6d87eb554 100644
--- a/mirai-core-api/src/commonMain/kotlin/message/code/internal/impl.kt
+++ b/mirai-core-api/src/commonMain/kotlin/message/code/internal/impl.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019-2020 Mamoe Technologies and contributors.
+ * Copyright 2019-2021 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.
@@ -13,7 +13,6 @@ package net.mamoe.mirai.message.code.internal
 
 import net.mamoe.mirai.contact.Contact
 import net.mamoe.mirai.message.data.*
-import net.mamoe.mirai.utils.MiraiInternalApi
 
 
 internal fun String.parseMiraiCodeImpl(contact: Contact?): MessageChain = buildMessageChain {
@@ -38,7 +37,7 @@ internal fun String.parseMiraiCodeImpl(contact: Contact?): MessageChain = buildM
     }
 }
 
-internal fun String.forEachMiraiCode(block: (origin: String, name: String?, args: String) -> Unit) {
+private fun String.forEachMiraiCode(block: (origin: String, name: String?, args: String) -> Unit) {
     var pos = 0
     var lastPos = 0
     val len = length - 7 // [mirai:
@@ -98,7 +97,7 @@ internal fun String.forEachMiraiCode(block: (origin: String, name: String?, args
     }
 }
 
-internal object MiraiCodeParsers : Map<String, MiraiCodeParser> by mapOf(
+private object MiraiCodeParsers : Map<String, MiraiCodeParser> by mapOf(
     "at" to MiraiCodeParser(Regex("""(\d*)""")) { (target) ->
         At(target.toLong())
     },
@@ -128,13 +127,12 @@ internal object MiraiCodeParsers : Map<String, MiraiCodeParser> by mapOf(
     }
 )
 
-internal class MiraiCodeParser(
+private class MiraiCodeParser(
     val argsRegex: Regex,
     val mapper: Contact?.(MatchResult.Destructured) -> Message?
 )
 
-@MiraiInternalApi
-public fun StringBuilder.appendAsMiraiCode(value: String): StringBuilder = apply {
+internal fun StringBuilder.appendStringAsMiraiCode(value: String): StringBuilder = apply {
     value.forEach { char ->
         when (char) {
             '[', ']',
@@ -148,9 +146,8 @@ public fun StringBuilder.appendAsMiraiCode(value: String): StringBuilder = apply
     }
 }
 
-@Suppress("RegExpRedundantEscape")
-internal val DECODE_MIRAI_CODE_REGEX = """\\.""".toRegex()
-internal val DECODE_MIRAI_CODE_TRANSLATOR: (MatchResult) -> String = {
+private val DECODE_MIRAI_CODE_REGEX = """\\.""".toRegex()
+private val DECODE_MIRAI_CODE_TRANSLATOR: (MatchResult) -> String = {
     when (it.value[1]) {
         'n' -> "\n"
         'r' -> "\r"
@@ -159,4 +156,4 @@ internal val DECODE_MIRAI_CODE_TRANSLATOR: (MatchResult) -> String = {
     }
 }
 
-internal fun String.decodeMiraiCode() = replace(DECODE_MIRAI_CODE_REGEX, DECODE_MIRAI_CODE_TRANSLATOR)
+private fun String.decodeMiraiCode() = replace(DECODE_MIRAI_CODE_REGEX, DECODE_MIRAI_CODE_TRANSLATOR)
diff --git a/mirai-core-api/src/commonMain/kotlin/message/data/HummerMessage.kt b/mirai-core-api/src/commonMain/kotlin/message/data/HummerMessage.kt
index 8fc3bebdf..3c30310f4 100644
--- a/mirai-core-api/src/commonMain/kotlin/message/data/HummerMessage.kt
+++ b/mirai-core-api/src/commonMain/kotlin/message/data/HummerMessage.kt
@@ -16,7 +16,7 @@ package net.mamoe.mirai.message.data
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import net.mamoe.mirai.message.code.CodableMessage
-import net.mamoe.mirai.message.code.internal.appendAsMiraiCode
+import net.mamoe.mirai.message.code.internal.appendStringAsMiraiCode
 import net.mamoe.mirai.message.data.VipFace.Kind
 import net.mamoe.mirai.utils.MiraiExperimentalApi
 import net.mamoe.mirai.utils.MiraiInternalApi
@@ -173,7 +173,7 @@ public data class PokeMessage @MiraiInternalApi constructor(
 
     @MiraiExperimentalApi
     override fun appendMiraiCodeTo(builder: StringBuilder) {
-        builder.append("[mirai:poke:").appendAsMiraiCode(name)
+        builder.append("[mirai:poke:").appendStringAsMiraiCode(name)
             .append(',').append(pokeType).append(',').append(id)
             .append(']')
     }
diff --git a/mirai-core-api/src/commonMain/kotlin/message/data/MessageChain.kt b/mirai-core-api/src/commonMain/kotlin/message/data/MessageChain.kt
index 567b734ad..9e856436e 100644
--- a/mirai-core-api/src/commonMain/kotlin/message/data/MessageChain.kt
+++ b/mirai-core-api/src/commonMain/kotlin/message/data/MessageChain.kt
@@ -24,6 +24,7 @@ import kotlinx.serialization.json.Json
 import net.mamoe.mirai.event.events.MessageEvent
 import net.mamoe.mirai.message.MessageSerializers
 import net.mamoe.mirai.message.code.CodableMessage
+import net.mamoe.mirai.message.code.MiraiCode
 import net.mamoe.mirai.message.data.MessageSource.Key.quote
 import net.mamoe.mirai.message.data.MessageSource.Key.recall
 import net.mamoe.mirai.utils.MiraiExperimentalApi
@@ -60,9 +61,10 @@ import kotlin.streams.asSequence
  * @see orElse 属性委托扩展
  * @see getValue 属性委托扩展
  * @see flatten 扁平化
+ *
+ * @see MiraiCode mirai 码
  */
 @Serializable(MessageChain.Serializer::class)
-@Suppress("FunctionName", "DeprecatedCallableAddReplaceWith", "INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
 public interface MessageChain : Message, List<SingleMessage>, RandomAccess, CodableMessage {
     /**
      * 元素数量. [EmptyMessageChain] 不参加计数.
diff --git a/mirai-core-api/src/commonMain/kotlin/message/data/PlainText.kt b/mirai-core-api/src/commonMain/kotlin/message/data/PlainText.kt
index d78f28ca0..47a81a994 100644
--- a/mirai-core-api/src/commonMain/kotlin/message/data/PlainText.kt
+++ b/mirai-core-api/src/commonMain/kotlin/message/data/PlainText.kt
@@ -16,7 +16,7 @@ package net.mamoe.mirai.message.data
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import net.mamoe.mirai.message.code.CodableMessage
-import net.mamoe.mirai.message.code.internal.appendAsMiraiCode
+import net.mamoe.mirai.message.code.internal.appendStringAsMiraiCode
 import net.mamoe.mirai.utils.MiraiExperimentalApi
 
 /**
@@ -37,7 +37,7 @@ public data class PlainText(
 
     @MiraiExperimentalApi
     override fun appendMiraiCodeTo(builder: StringBuilder) {
-        builder.appendAsMiraiCode(content)
+        builder.appendStringAsMiraiCode(content)
     }
 
     public companion object {
diff --git a/mirai-core-api/src/commonMain/kotlin/message/data/RichMessage.kt b/mirai-core-api/src/commonMain/kotlin/message/data/RichMessage.kt
index e3a181438..fccb12731 100644
--- a/mirai-core-api/src/commonMain/kotlin/message/data/RichMessage.kt
+++ b/mirai-core-api/src/commonMain/kotlin/message/data/RichMessage.kt
@@ -16,7 +16,7 @@ package net.mamoe.mirai.message.data
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import net.mamoe.mirai.message.code.CodableMessage
-import net.mamoe.mirai.message.code.internal.appendAsMiraiCode
+import net.mamoe.mirai.message.code.internal.appendStringAsMiraiCode
 import net.mamoe.mirai.utils.MiraiExperimentalApi
 import net.mamoe.mirai.utils.safeCast
 import kotlin.annotation.AnnotationTarget.*
@@ -106,7 +106,7 @@ public data class LightApp(override val content: String) : RichMessage, CodableM
 
     @MiraiExperimentalApi
     override fun appendMiraiCodeTo(builder: StringBuilder) {
-        builder.append("[mirai:app:").appendAsMiraiCode(content).append(']')
+        builder.append("[mirai:app:").appendStringAsMiraiCode(content).append(']')
     }
 }
 
@@ -167,7 +167,7 @@ public interface ServiceMessage : RichMessage, CodableMessage {
 
     @MiraiExperimentalApi
     override fun appendMiraiCodeTo(builder: StringBuilder) {
-        builder.append("[mirai:service:").append(serviceId).append(',').appendAsMiraiCode(content).append(']')
+        builder.append("[mirai:service:").append(serviceId).append(',').appendStringAsMiraiCode(content).append(']')
     }
 }
 
diff --git a/mirai-core-api/src/commonTest/kotlin/message/code/TestMiraiCode.kt b/mirai-core-api/src/commonTest/kotlin/message/code/TestMiraiCode.kt
index 2a5736c38..01830b038 100644
--- a/mirai-core-api/src/commonTest/kotlin/message/code/TestMiraiCode.kt
+++ b/mirai-core-api/src/commonTest/kotlin/message/code/TestMiraiCode.kt
@@ -9,6 +9,7 @@
 
 package net.mamoe.mirai.message.code
 
+import net.mamoe.mirai.message.code.MiraiCode.parseMiraiCode
 import net.mamoe.mirai.message.data.*
 import org.junit.jupiter.api.Test
 import kotlin.test.assertEquals