fix: complete 2025-11-25 model spec conformance

Author: DaleSeo

conformance/src/bin/client.rs

@@ -121,7 +121,9 @@ impl ClientHandler for ElicitationDefaultsClientHandler {
             _ => Some(json!({})),
         };
         let mut result = ElicitResult::new(ElicitationAction::Accept);
-        result.content = content;
+        if let Some(c) = content {
+            result = result.with_content(c);
+        }
         Ok(result)
     }
 }

crates/rmcp/CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- [**breaking**] align `TaskStatusNotificationParam` with `NotificationParams & Task`; construct it with `TaskStatusNotificationParam::new(task)` or `task.into()`, use `.task` when exact `Task` identity matters, and rely on `Deref` for existing task field access ([#927](https://github.com/modelcontextprotocol/rust-sdk/pull/927))
+- [**breaking**] require `ToolResultContent.content` in sampling tool results; send `content: []` for empty results. `CallToolResult` missing-content compatibility is unchanged ([#927](https://github.com/modelcontextprotocol/rust-sdk/pull/927))
+
 ## [1.8.0](https://github.com/modelcontextprotocol/rust-sdk/compare/rmcp-v1.7.0...rmcp-v1.8.0) - 2026-06-22
 
 ### Added

crates/rmcp/src/handler/client.rs

@@ -128,7 +128,7 @@ pub trait ClientHandler: Sized + Send + Sync + 'static {
     ///
     /// # Example
     /// ```rust,ignore
-    /// use rmcp::model::CreateElicitationRequestParam;
+    /// use rmcp::model::ElicitRequestParams;
     /// use rmcp::{
     ///     model::ErrorData as McpError,
     ///     model::*,
@@ -139,11 +139,11 @@ pub trait ClientHandler: Sized + Send + Sync + 'static {
     /// impl ClientHandler for MyClient {
     ///  async fn create_elicitation(
     ///     &self,
-    ///     request: CreateElicitationRequestParam,
+    ///     request: ElicitRequestParams,
     ///     context: RequestContext<RoleClient>,
     ///  ) -> Result<ElicitResult, McpError> {
     ///     match request {
-    ///         CreateElicitationRequestParam::FormElicitationParam {meta, message, requested_schema,} => {
+    ///         ElicitRequestParams::FormElicitationParam {meta, message, requested_schema,} => {
     ///            // Display message to user and collect input according to requested_schema
     ///           let user_input = get_user_input(message, requested_schema).await?;
     ///          Ok(ElicitResult {
@@ -152,7 +152,7 @@ pub trait ClientHandler: Sized + Send + Sync + 'static {
     ///              meta: None,
     ///          })
     ///         }
-    ///         CreateElicitationRequestParam::UrlElicitationParam {meta, message, url, elicitation_id,} => {
+    ///         ElicitRequestParams::UrlElicitationParam {meta, message, url, elicitation_id,} => {
     ///           // Open URL in browser for user to complete elicitation
     ///           open_url_in_browser(url).await?;
     ///          Ok(ElicitResult {

crates/rmcp/src/model.rs

@@ -1,4 +1,8 @@
-use std::{borrow::Cow, sync::Arc};
+use std::{
+    borrow::Cow,
+    ops::{Deref, DerefMut},
+    sync::Arc,
+};
 mod annotated;
 mod capabilities;
 mod content;
@@ -702,6 +706,7 @@ impl CustomResult {
 pub struct CancelledNotificationParam {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub request_id: Option<RequestId>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub reason: Option<String>,
     #[serde(rename = "_meta", skip_serializing_if = "Option::is_none")]
     pub meta: Option<Meta>,
@@ -2417,7 +2422,6 @@ impl Reference {
         Self::Prompt(PromptReference {
             name: name.into(),
             title: None,
-            meta: None,
         })
     }
 
@@ -2474,8 +2478,6 @@ pub struct PromptReference {
     pub name: String,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub title: Option<String>,
-    #[serde(rename = "_meta", skip_serializing_if = "Option::is_none")]
-    pub meta: Option<Meta>,
 }
 
 impl PromptReference {
@@ -2484,7 +2486,6 @@ impl PromptReference {
         Self {
             name: name.into(),
             title: None,
-            meta: None,
         }
     }
 
@@ -2561,12 +2562,20 @@ pub type ListRootsRequest = RequestNoParam<ListRootsRequestMethod>;
 #[non_exhaustive]
 pub struct ListRootsResult {
     pub roots: Vec<Root>,
+    #[serde(rename = "_meta", skip_serializing_if = "Option::is_none")]
+    pub meta: Option<Meta>,
 }
 
 impl ListRootsResult {
     /// Creates a new `ListRootsResult` with the given roots.
     pub fn new(roots: Vec<Root>) -> Self {
-        Self { roots }
+        Self { roots, meta: None }
+    }
+
+    /// Sets the protocol-level metadata for this result.
+    pub fn with_meta(mut self, meta: Meta) -> Self {
+        self.meta = Some(meta);
+        self
     }
 }
 
@@ -3370,7 +3379,47 @@ const_string!(TaskStatusNotificationMethod = "notifications/tasks/status");
 /// Parameters for a task status notification (spec `TaskStatusNotificationParams`).
 ///
 /// The task fields are flattened at the top level: `NotificationParams & Task`.
-pub type TaskStatusNotificationParam = crate::model::Task;
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+#[non_exhaustive]
+pub struct TaskStatusNotificationParam {
+    #[serde(rename = "_meta", default, skip_serializing_if = "Option::is_none")]
+    pub meta: Option<Meta>,
+    #[serde(flatten)]
+    pub task: crate::model::Task,
+}
+
+impl TaskStatusNotificationParam {
+    pub fn new(task: crate::model::Task) -> Self {
+        Self { meta: None, task }
+    }
+
+    pub fn with_meta(mut self, meta: Meta) -> Self {
+        self.meta = Some(meta);
+        self
+    }
+}
+
+impl From<crate::model::Task> for TaskStatusNotificationParam {
+    fn from(task: crate::model::Task) -> Self {
+        Self::new(task)
+    }
+}
+
+impl Deref for TaskStatusNotificationParam {
+    type Target = crate::model::Task;
+
+    fn deref(&self) -> &Self::Target {
+        &self.task
+    }
+}
+
+impl DerefMut for TaskStatusNotificationParam {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.task
+    }
+}
 
 pub type TaskStatusNotification =
     Notification<TaskStatusNotificationMethod, TaskStatusNotificationParam>;
@@ -3613,6 +3662,30 @@ mod tests {
 
     use super::*;
 
+    #[test]
+    #[allow(deprecated)]
+    fn deprecated_aliases_still_resolve() {
+        // 하위호환: 구 이름이 새 타입으로 여전히 resolve되는지 확인.
+        let _: CreateElicitationResult = ElicitResult::new(ElicitationAction::Accept);
+        let _: GetTaskResultParams = GetTaskPayloadParams::new("task-1");
+        let _: ResourceReference = ResourceTemplateReference::new("res://x");
+    }
+
+    #[test]
+    fn cancelled_notification_request_id_is_optional_on_wire() {
+        // None → requestId 생략
+        let p = CancelledNotificationParam::new(None, Some("user cancelled".into()));
+        let v = serde_json::to_value(&p).unwrap();
+        assert!(v.get("requestId").is_none());
+
+        // Some → requestId 방출 + 라운드트립
+        let p = CancelledNotificationParam::new(Some(RequestId::Number(1)), None);
+        let v = serde_json::to_value(&p).unwrap();
+        assert_eq!(v["requestId"], json!(1));
+        let back: CancelledNotificationParam = serde_json::from_value(v).unwrap();
+        assert_eq!(back.request_id, Some(RequestId::Number(1)));
+    }
+
     #[test]
     fn test_notification_serde() {
         let raw = json!( {

crates/rmcp/src/model/content.rs

@@ -195,7 +195,6 @@ pub struct ToolResultContent {
     #[serde(rename = "_meta", skip_serializing_if = "Option::is_none")]
     pub meta: Option<Meta>,
     pub tool_use_id: String,
-    #[serde(default, skip_serializing_if = "Vec::is_empty")]
     pub content: Vec<ContentBlock>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub structured_content: Option<super::JsonObject>,

crates/rmcp/src/model/task.rs

@@ -138,12 +138,20 @@ impl Task {
 #[non_exhaustive]
 pub struct CreateTaskResult {
     pub task: Task,
+    #[serde(rename = "_meta", skip_serializing_if = "Option::is_none")]
+    pub meta: Option<Meta>,
 }
 
 impl CreateTaskResult {
     /// Create a new CreateTaskResult.
     pub fn new(task: Task) -> Self {
-        Self { task }
+        Self { task, meta: None }
+    }
+
+    /// Sets the protocol-level metadata for this result.
+    pub fn with_meta(mut self, meta: Meta) -> Self {
+        self.meta = Some(meta);
+        self
     }
 }
 
@@ -224,27 +232,3 @@ impl CancelTaskResult {
         Self { meta: None, task }
     }
 }
-
-/// Paginated list of tasks
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
-#[serde(rename_all = "camelCase")]
-#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
-#[non_exhaustive]
-pub struct TaskList {
-    pub tasks: Vec<Task>,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub next_cursor: Option<String>,
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub total: Option<u64>,
-}
-
-impl TaskList {
-    /// Create a new TaskList.
-    pub fn new(tasks: Vec<Task>) -> Self {
-        Self {
-            tasks,
-            next_cursor: None,
-            total: None,
-        }
-    }
-}

crates/rmcp/tests/test_completion.rs

@@ -156,14 +156,18 @@ fn test_completion_serialization_format() {
 
 #[test]
 fn test_resource_reference() {
-    // Test that ResourceTemplateReference works correctly
-    let resource_ref = ResourceTemplateReference::new("test://uri");
-
-    // Test that ResourceTemplateReference works correctly
-    let another_ref = ResourceTemplateReference::new("test://uri");
-
-    // They should be equivalent
-    assert_eq!(resource_ref.uri, another_ref.uri);
+    // ResourceTemplateReference가 `ref/resource` 와이어 태그로 직렬화/역직렬화되는지 확인
+    let reference = Reference::for_resource("test://uri");
+
+    let json = serde_json::to_value(&reference).unwrap();
+    assert_eq!(json["type"], "ref/resource");
+    assert_eq!(json["uri"], "test://uri");
+
+    let back: Reference = serde_json::from_value(json).unwrap();
+    match back {
+        Reference::Resource(r) => assert_eq!(r.uri, "test://uri"),
+        other => panic!("expected Reference::Resource, got {other:?}"),
+    }
 }
 
 #[test]