Task Context

TaskContext

Context object provided to the TaskHandler. Contains the information needed for the handler to process the task.

{
  /**
   * The current state of the task when the handler is invoked or resumed.
   * This is a snapshot - the latest state may need to be reloaded during async operations.
   */
  task: Task;

  /**
   * The specific user message that triggered this handler invocation or resumption.
   */
  userMessage: Message;

  /**
   * Function to check if cancellation has been requested for this task.
   * Handlers should check this periodically during long-running operations.
   * @returns True if cancellation has been requested, false otherwise.
   */
  isCancelled(): boolean;

  /**
   * The message history associated with the task up to the point the handler is invoked.
   */
  history: Message[];
}

TaskHandler

The current state of the task when the handler is invoked or resumed. This is a snapshot - the latest state may need to be reloaded during async operations. / task: Task;

/** The specific user message that triggered this handler invocation or resumption. / userMessage: Message;

/** Function to check if cancellation has been requested for this task. Handlers should check this periodically during long-running operations. @returns True if cancellation has been requested, false otherwise. / isCancelled(): boolean;

/** The message history associated with the task up to the point the handler is invoked. / history: Message[]; }

/** Defines the signature for a task handler function.

Handlers are implemented as async generators. They receive context about the task and the triggering message. They perform work and yield status or artifact updates (TaskYieldUpdate). The server consumes these yields, updates the task state in the store, and streams events if applicable.

@param context The TaskContext object containing task details and state. @yields Updates to the task's status or artifacts. @returns Optionally returns the final complete Task object (needed for non-streaming 'tasks/send'). If void is returned, the server uses the last known state after processing all yields.

task: Task;