feat(task): add task support (SEP-1686)

Author: jokemanfire

crates/rmcp/src/model.rs

@@ -6,6 +6,7 @@ mod elicitation_schema;
 mod extension;
 mod meta;
 mod prompt;
+mod task;
 mod resource;
 mod serde_impl;
 mod tool;
@@ -17,6 +18,7 @@ pub use extension::*;
 pub use meta::*;
 pub use prompt::*;
 pub use resource::*;
+pub use task::*;
 use serde::{Deserialize, Serialize, de::DeserializeOwned};
 use serde_json::Value;
 pub use tool::*;

crates/rmcp/src/model/task.rs

@@ -0,0 +1,270 @@
+use serde::{Deserialize, Serialize};
+use serde_json::Value;
+
+use super::{JsonObject, Meta};
+
+/// Task lifecycle status
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub enum TaskStatus {
+	/// Created but not started yet
+	Pending,
+	/// Currently running
+	Running,
+	/// Waiting for dependencies or external input
+	Waiting,
+	/// Cancellation requested and in progress
+	Cancelling,
+	/// Completed successfully
+	Succeeded,
+	/// Completed with failure
+	Failed,
+	/// Cancelled before completion
+	Cancelled,
+}
+
+/// High-level task kind. Exact set may evolve with the SEP.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize,Default)]
+#[serde(rename_all = "snake_case")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub enum TaskKind {
+    #[default]
+	Generation,
+	Retrieval,
+	Aggregation,
+	Orchestration,
+	ToolCall,
+	/// Custom kind identifier
+	Custom(String),
+}
+
+/// Progress information for long-running tasks
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct TaskProgress {
+	/// Percentage progress in the range [0.0, 100.0]
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub percent: Option<f32>,
+	/// Current stage identifier
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub stage: Option<String>,
+	/// Human-readable status message
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub message: Option<String>,
+	/// Arbitrary structured details, protocol-specific
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub details: Option<Value>,
+}
+
+/// Error information for failed tasks
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct TaskError {
+	/// Machine-readable error code
+	pub code: String,
+	/// Human-readable error message
+	pub message: String,
+	/// Whether the operation can be retried safely
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub retryable: Option<bool>,
+	/// Arbitrary error data for debugging
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub data: Option<Value>,
+}
+
+/// Final result for a succeeded task
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct TaskResult {
+	/// MIME type or custom content-type identifier
+	pub content_type: String,
+	/// The actual result payload
+	pub value: Value,
+	/// Optional short summary for UI
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub summary: Option<String>,
+}
+
+/// Primary Task object used across client/server
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct Task {
+	/// Unique task identifier
+	pub id: String,
+	/// Task kind/category
+	pub kind: TaskKind,
+	/// Current status
+	pub status: TaskStatus,
+	/// ISO8601 creation time
+	pub created_at: String,
+	/// ISO8601 last update time
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub updated_at: Option<String>,
+	/// ISO8601 start time
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub started_at: Option<String>,
+	/// ISO8601 completion time
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub completed_at: Option<String>,
+	/// Parent task identifier for hierarchical tasks
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub parent_id: Option<String>,
+	/// List of prerequisite task ids
+	#[serde(default, skip_serializing_if = "Vec::is_empty")]
+	pub depends_on: Vec<String>,
+	/// Optional labels for filtering and grouping
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub labels: Option<Vec<String>>,
+	/// Immutable metadata provided at creation
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub metadata: Option<Value>,
+	/// Mutable runtime state exposed to clients
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub runtime_state: Option<Value>,
+	/// Input parameters for this task
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub input: Option<Value>,
+	/// Progress info when running
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub progress: Option<TaskProgress>,
+	/// Final result when succeeded
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub result: Option<TaskResult>,
+	/// Error information when failed
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub error: Option<TaskError>,
+	/// True if a cancellation has been requested
+	#[serde(default)]
+	pub cancellation_requested: bool,
+	/// Scheduling priority; larger means higher priority (convention)
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub priority: Option<i32>,
+	/// Batch/group identifier for bulk operations
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub batch_group: Option<String>,
+	/// Trace identifier for observability systems
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub trace_id: Option<String>,
+	/// Protocol-level metadata for the task object
+	#[serde(rename = "_meta", skip_serializing_if = "Option::is_none")]
+	pub meta: Option<Meta>,
+	/// Reserved for future SEP extensions
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub extensions: Option<JsonObject>,
+}
+
+/// Query filter for listing tasks
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct TaskQuery {
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub ids: Option<Vec<String>>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub status: Option<Vec<TaskStatus>>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub kind: Option<Vec<TaskKind>>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub parent_id: Option<String>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub labels_any: Option<Vec<String>>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub labels_all: Option<Vec<String>>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub created_after: Option<String>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub created_before: Option<String>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub limit: Option<u32>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub cursor: Option<String>,
+}
+
+/// Paginated list of tasks
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+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>,
+}
+
+/// Request payload to create a new task
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct TaskCreateRequest {
+	pub kind: TaskKind,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub input: Option<Value>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub parent_id: Option<String>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub depends_on: Option<Vec<String>>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub labels: Option<Vec<String>>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub metadata: Option<Value>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub priority: Option<i32>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub batch_group: Option<String>,
+	/// Protocol-level metadata for the request object
+	#[serde(rename = "_meta", skip_serializing_if = "Option::is_none")]
+	pub meta: Option<Meta>,
+	/// Reserved for future SEP extensions
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub extensions: Option<JsonObject>,
+}
+
+/// Request payload to update a task's runtime fields
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct TaskUpdateRequest {
+	pub id: String,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub runtime_state: Option<Value>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub cancellation_requested: Option<bool>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub labels: Option<Vec<String>>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub priority: Option<i32>,
+}
+
+/// Incremental progress event for streaming updates
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct TaskProgressEvent {
+	pub id: String,
+	pub progress: TaskProgress,
+	/// ISO8601 timestamp for the event
+	pub timestamp: String,
+}
+
+/// Terminal event signaling task completion
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+pub struct TaskCompletionEvent {
+	pub id: String,
+	/// Allowed values: Succeeded, Failed, Cancelled
+	pub status: TaskStatus,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub result: Option<TaskResult>,
+	#[serde(skip_serializing_if = "Option::is_none")]
+	pub error: Option<TaskError>,
+	/// ISO8601 timestamp for the event
+	pub timestamp: String,
+}
+