Fix types and add test for common, completion, content, resources

Author: devcrocod

kotlin-sdk-core/api/kotlin-sdk-core.api

@@ -38,6 +38,11 @@ internal object ErrorCodeSerializer : KSerializer<ErrorCode> {
     }
 }
 
+@Deprecated(
+    message = "Use `MethodSerializer` instead",
+    replaceWith = ReplaceWith("MethodSerializer"),
+    level = DeprecationLevel.WARNING,
+)
 internal object RequestMethodSerializer : KSerializer<Method> {
     override val descriptor: SerialDescriptor =
         PrimitiveSerialDescriptor("io.modelcontextprotocol.kotlin.sdk.Method", PrimitiveKind.STRING)

kotlin-sdk-core/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/types.util.kt

@@ -2,6 +2,7 @@ package io.modelcontextprotocol.kotlin.sdk.types
 
 import kotlinx.serialization.EncodeDefault
 import kotlinx.serialization.ExperimentalSerializationApi
+import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.json.JsonObject
 
@@ -29,6 +30,7 @@ public data class CompleteRequestParams(
     val argument: Argument,
     val ref: Reference,
     val context: Context? = null,
+    @SerialName("_meta")
     override val meta: RequestMeta? = null,
 ) : RequestParams {
     /**
@@ -62,8 +64,11 @@ public data class CompleteRequestParams(
  * @property meta Optional metadata for this response. See MCP specification for details on _meta usage.
  */
 @Serializable
-public data class CompleteResult(public val completion: Completion, override val meta: JsonObject? = null) :
-    ServerResult {
+public data class CompleteResult(
+    public val completion: Completion,
+    @SerialName("_meta")
+    override val meta: JsonObject? = null,
+) : ServerResult {
 
     /**
      * Completion options and pagination information.

kotlin-sdk-core/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/types/completion.kt

@@ -4,15 +4,34 @@ package io.modelcontextprotocol.kotlin.sdk.types
 
 import kotlinx.serialization.EncodeDefault
 import kotlinx.serialization.ExperimentalSerializationApi
+import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.json.JsonObject
 
 @Serializable
+public enum class ContentTypes(public val value: String) {
+    @SerialName("text")
+    TEXT("text"),
+
+    @SerialName("image")
+    IMAGE("image"),
+
+    @SerialName("audio")
+    AUDIO("audio"),
+
+    @SerialName("resource_link")
+    RESOURCE_LINK("resource_link"),
+
+    @SerialName("resource")
+    EMBEDDED_RESOURCE("resource"),
+}
+
+@Serializable(with = ContentBlockPolymorphicSerializer::class)
 public sealed interface ContentBlock : WithMeta {
-    public val type: String
+    public val type: ContentTypes
 }
 
-@Serializable
+@Serializable(with = MediaContentPolymorphicSerializer::class)
 public sealed interface MediaContent : ContentBlock
 
 /**
@@ -27,10 +46,11 @@ public sealed interface MediaContent : ContentBlock
 public data class TextContent(
     val text: String,
     val annotations: Annotations? = null,
+    @SerialName("_meta")
     override val meta: JsonObject? = null,
 ) : MediaContent {
     @EncodeDefault
-    public override val type: String = "text"
+    public override val type: ContentTypes = ContentTypes.TEXT
 }
 
 /**
@@ -47,10 +67,11 @@ public data class ImageContent(
     val data: String,
     val mimeType: String,
     val annotations: Annotations? = null,
+    @SerialName("_meta")
     override val meta: JsonObject? = null,
 ) : MediaContent {
     @EncodeDefault
-    public override val type: String = "image"
+    public override val type: ContentTypes = ContentTypes.IMAGE
 }
 
 /**
@@ -67,10 +88,11 @@ public data class AudioContent(
     val data: String,
     val mimeType: String,
     val annotations: Annotations? = null,
+    @SerialName("_meta")
     override val meta: JsonObject? = null,
 ) : MediaContent {
     @EncodeDefault
-    public override val type: String = "audio"
+    public override val type: ContentTypes = ContentTypes.AUDIO
 }
 
 /**
@@ -111,11 +133,12 @@ public data class ResourceLink(
     val icons: List<Icon>? = null,
     val description: String? = null,
     val annotations: Annotations? = null,
+    @SerialName("_meta")
     override val meta: JsonObject? = null,
 ) : ContentBlock,
     ResourceLike {
     @EncodeDefault
-    public override val type: String = "resource_link"
+    public override val type: ContentTypes = ContentTypes.RESOURCE_LINK
 }
 
 /**
@@ -132,8 +155,9 @@ public data class ResourceLink(
 public data class EmbeddedResource(
     val resource: ResourceContents,
     val annotations: Annotations? = null,
+    @SerialName("_meta")
     override val meta: JsonObject? = null,
 ) : ContentBlock {
     @EncodeDefault
-    public override val type: String = "resource"
+    public override val type: ContentTypes = ContentTypes.EMBEDDED_RESOURCE
 }

kotlin-sdk-core/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/types/content.kt

@@ -5,7 +5,7 @@ import kotlinx.serialization.Serializable
 /**
  * Represents a method in the protocol, which can be predefined or custom.
  */
-@Serializable // TODO: Custom serializer or use SerialName
+@Serializable(with = MethodSerializer::class)
 public sealed interface Method {
     public val value: String
 

kotlin-sdk-core/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/types/methods.kt

@@ -118,8 +118,8 @@ public data class ResourceTemplateReference(val uri: String) : Reference {
  * @property mimeType The MIME type of this resource, if known.
  * @property meta Optional metadata for this response.
  */
-@Serializable
-public sealed interface ResourceContents : WithMeta { // TODO: need serializer
+@Serializable(with = ResourceContentsPolymorphicSerializer::class)
+public sealed interface ResourceContents : WithMeta {
     public val uri: String
     public val mimeType: String?
 }
@@ -137,6 +137,7 @@ public data class TextResourceContents(
     val text: String,
     override val uri: String,
     override val mimeType: String? = null,
+    @SerialName("_meta")
     override val meta: JsonObject? = null,
 ) : ResourceContents
 
@@ -152,6 +153,7 @@ public data class BlobResourceContents(
     val blob: String,
     override val uri: String,
     override val mimeType: String? = null,
+    @SerialName("_meta")
     override val meta: JsonObject? = null,
 ) : ResourceContents
 
@@ -165,6 +167,7 @@ public data class BlobResourceContents(
 public data class UnknownResourceContents(
     override val uri: String,
     override val mimeType: String? = null,
+    @SerialName("_meta")
     override val meta: JsonObject? = null,
 ) : ResourceContents