Provides an interface for pluggable task storage implementations in MCP servers.

[Experimental("MCPEXP001", UrlFormat = "https://github.com/modelcontextprotocol/csharp-sdk/blob/main/docs/list-of-diagnostics.md#mcpexp001")]
public interface IMcpTaskStore

Methods

CancelTaskAsync(string, string?, CancellationToken)

Attempts to cancel a task, transitioning it to Cancelled status.

Task<McpTask> CancelTaskAsync(string taskId, string? sessionId = null, CancellationToken cancellationToken = default)

Parameters

taskId string

The unique identifier of the task to cancel.

sessionId string

Optional session identifier for access control.

cancellationToken CancellationToken

Cancellation token for the operation.

Returns

Task<McpTask>

The updated McpTask. If the task is already in a terminal state (Completed, Failed, or Cancelled), the task is returned unchanged.

CreateTaskAsync(McpTaskMetadata, RequestId, JsonRpcRequest, string?, CancellationToken)

Creates a new task for tracking an asynchronous operation.

Task<McpTask> CreateTaskAsync(McpTaskMetadata taskParams, RequestId requestId, JsonRpcRequest request, string? sessionId = null, CancellationToken cancellationToken = default)

Parameters

taskParams McpTaskMetadata

Metadata for the task, including requested TTL.

requestId RequestId

The JSON-RPC request ID that initiated this task.

request JsonRpcRequest

The original JSON-RPC request that triggered task creation.

sessionId string

Optional session identifier for multi-session isolation.

cancellationToken CancellationToken

Cancellation token for the operation.

Returns

Task<McpTask>

A new McpTask with a unique task ID, initial status of Working, and the actual TTL that will be used (which may differ from the requested TTL).

GetTaskAsync(string, string?, CancellationToken)

Retrieves a task by its unique identifier.

Task<McpTask?> GetTaskAsync(string taskId, string? sessionId = null, CancellationToken cancellationToken = default)

Parameters

taskId string

The unique identifier of the task to retrieve.

sessionId string

Optional session identifier for access control.

cancellationToken CancellationToken

Cancellation token for the operation.

Returns

Task<McpTask>

The McpTask if found and accessible, otherwise null.

GetTaskResultAsync(string, string?, CancellationToken)

Retrieves the stored result of a completed or failed task.

Task<JsonElement> GetTaskResultAsync(string taskId, string? sessionId = null, CancellationToken cancellationToken = default)

Parameters

taskId string

The unique identifier of the task.

sessionId string

Optional session identifier for access control.

cancellationToken CancellationToken

Cancellation token for the operation.

Returns

Task<JsonElement>

The stored operation result as a JSON element.

ListTasksAsync(string?, string?, CancellationToken)

Lists tasks with pagination support.

Task<ListTasksResult> ListTasksAsync(string? cursor = null, string? sessionId = null, CancellationToken cancellationToken = default)

Parameters

cursor string

Optional cursor for pagination, from a previous call's nextCursor value.

sessionId string

Optional session identifier for filtering tasks by session.

cancellationToken CancellationToken

Cancellation token for the operation.

Returns

Task<ListTasksResult>

A ListTasksResult containing the tasks and an optional cursor for the next page.

StoreTaskResultAsync(string, McpTaskStatus, JsonElement, string?, CancellationToken)

Stores the final result of a task that has reached a terminal status.

Task<McpTask> StoreTaskResultAsync(string taskId, McpTaskStatus status, JsonElement result, string? sessionId = null, CancellationToken cancellationToken = default)

Parameters

taskId string

The unique identifier of the task.

status McpTaskStatus

The terminal status: Completed or Failed.

result JsonElement

The operation result to store as a JSON element.

sessionId string

Optional session identifier for access control.

cancellationToken CancellationToken

Cancellation token for the operation.

Returns

Task<McpTask>

The updated McpTask with the new status and result stored.

UpdateTaskStatusAsync(string, McpTaskStatus, string?, string?, CancellationToken)

Updates the status and optional status message of a task.

Task<McpTask> UpdateTaskStatusAsync(string taskId, McpTaskStatus status, string? statusMessage, string? sessionId = null, CancellationToken cancellationToken = default)

Parameters

taskId string

The unique identifier of the task.

status McpTaskStatus

The new status to set.

statusMessage string

Optional diagnostic message describing the status change.

sessionId string

Optional session identifier for access control.

cancellationToken CancellationToken

Cancellation token for the operation.

Returns

Task<McpTask>

The updated McpTask with the new status applied.