title: Server. Task Manager

A2A Node SDK - v0.1.0 / Modules / Server / TaskManager

Class: TaskManager

Server.TaskManager

Manages task lifecycle and state

The TaskManager is responsible for creating, updating, and managing tasks throughout their lifecycle. It provides methods for task creation, status updates, cancellation, and artifact management.

Example

// Create a task manager with in-memory storage
const taskStore = new InMemoryTaskStore();
const taskManager = new TaskManager(taskStore);
 
// Create a new task
const task = await taskManager.createTask({
  name: 'ProcessData',
  agentId: 'data-processor',
  parts: [{ type: 'text', content: 'Process this data', format: 'plain' }],
  expectedParts: 1,
  createdAt: new Date().toISOString(),
  updatedAt: new Date().toISOString()
});
 
console.log('Created task:', task.id);

Table of contents

Constructors

• constructor

Methods

• addArtifact
• cancelTask
• createTask
• getAggregator
• getArtifact
• getArtifacts
• getTask
• listActiveTasks
• updateTask
• updateTaskStatus

Constructors

constructor

• new TaskManager(taskStore, pushService?): TaskManager

Creates a new TaskManager

Parameters

Returns

TaskManager

Methods

addArtifact

▸ addArtifact(taskId, artifact): Promise<void>

Adds an artifact to a task

Artifacts represent files, data, or other content associated with a task. This method adds an artifact to a specific task.

Parameters

Returns

Promise<void>

Promise resolving when the artifact is added

Throws

If the task is not found

Example

await taskManager.addArtifact('task-123', {
  id: 'artifact-456',
  type: 'file',
  content: 'base64-encoded-file-data',
  createdAt: new Date().toISOString(),
  updatedAt: new Date().toISOString(),
  metadata: {
    filename: 'report.pdf',
    mimeType: 'application/pdf'
  }
});

cancelTask

▸ cancelTask(taskId): Promise<void>

Cancels a task

Cancels a task that is not already in a terminal state (completed, failed, or canceled). If a push service is configured, it will send a push notification about the cancellation.

Parameters

Returns

Promise<void>

Promise resolving when the task is canceled

Throws

If the task is not found

Throws

If the task is already in a terminal state

Example

try {
  await taskManager.cancelTask('task-123');
  console.log('Task canceled successfully');
} catch (error) {
  if (error instanceof InvalidTaskStateError) {
    console.error('Cannot cancel task in terminal state');
  } else {
    console.error('Error canceling task:', error);
  }
}

createTask

▸ createTask(task): Promise<Task>

Creates a new task

Creates a task with the provided parameters and initializes a result aggregator if expectedParts is specified.

Parameters

Returns

Promise<Task>

Promise resolving to the created task

Example

const task = await taskManager.createTask({
  name: 'ProcessImage',
  agentId: 'image-processor',
  parts: [{
    type: 'file',
    content: 'base64-encoded-image-data',
    mimeType: 'image/jpeg',
    name: 'image.jpg'
  }],
  expectedParts: 2,
  createdAt: new Date().toISOString(),
  updatedAt: new Date().toISOString()
});

getAggregator

▸ getAggregator(taskId): undefined | ResultAggregator

Gets the result aggregator for a task

Result aggregators collect and process task results, including handling streaming responses and combining multiple parts.

Parameters

Returns

undefined | ResultAggregator

The result aggregator for the task, or undefined if none exists

getArtifact

▸ getArtifact(taskId, artifactId): Promise<null | { content: Record<string, any> ; createdAt: string ; id: string ; type: "text" | "file" | "data" ; updatedAt: string }>

Gets a specific artifact for a task

Retrieves a specific artifact by ID from a specific task.

Parameters

Returns

Promise<null | { content: Record<string, any> ; createdAt: string ; id: string ; type: "text" | "file" | "data" ; updatedAt: string }>

Promise resolving to the artifact, or null if not found

Throws

If the task is not found

Example

const artifact = await taskManager.getArtifact('task-123', 'artifact-456');
if (artifact) {
  console.log('Found artifact:', artifact.id);
  console.log('Type:', artifact.type);
  console.log('Created at:', artifact.createdAt);
} else {
  console.log('Artifact not found');
}

getArtifacts

▸ getArtifacts(taskId): Promise<{ content: Record<string, any> ; createdAt: string ; id: string ; type: "text" | "file" | "data" ; updatedAt: string }[]>

Gets all artifacts for a task

Retrieves all artifacts associated with a specific task.

Parameters

Returns

Promise<{ content: Record<string, any> ; createdAt: string ; id: string ; type: "text" | "file" | "data" ; updatedAt: string }[]>

Promise resolving to an array of artifacts

Throws

If the task is not found

Example

const artifacts = await taskManager.getArtifacts('task-123');
console.log(`Task has ${artifacts.length} artifacts`);
 
// Process each artifact
for (const artifact of artifacts) {
  console.log(`Artifact ${artifact.id} of type ${artifact.type}`);
}

getTask

▸ getTask(taskId): Promise<Task>

Gets a task by ID

Retrieves a task from the task store by its ID.

Parameters

Returns

Promise<Task>

Promise resolving to the task

Throws

If the task is not found

Example

try {
  const task = await taskManager.getTask('task-123');
  console.log('Task status:', task.status);
} catch (error) {
  if (error instanceof TaskNotFoundError) {
    console.error('Task not found');
  } else {
    console.error('Error retrieving task:', error);
  }
}

listActiveTasks

▸ listActiveTasks(): Promise<Task[]>

Lists all active tasks

Retrieves all tasks that are not in a terminal state (completed, failed, or canceled). Active tasks include those with status ‘submitted’, ‘working’, or ‘input_required’.

Returns

Promise<Task[]>

Promise resolving to an array of active tasks

Example

const activeTasks = await taskManager.listActiveTasks();
console.log(`Found ${activeTasks.length} active tasks`);
 
// Process each active task
for (const task of activeTasks) {
  console.log(`Task ${task.id} is ${task.status}`);
}

updateTask

▸ updateTask(taskId, updates): Promise<Task>

Updates a task with new data

Updates a task with the provided partial task data and sets the updatedAt timestamp to the current time.

Parameters

Returns

Promise<Task>

Promise resolving to the updated task

Throws

If the task is not found

Example

const updatedTask = await taskManager.updateTask('task-123', {
  name: 'Updated Task Name',
  metadata: { priority: 'high' }
});

updateTaskStatus

▸ updateTaskStatus(taskId, status): Promise<Task>

Updates a task’s status

Updates the status of a task and sets the updatedAt timestamp to the current time.

Parameters

Returns

Promise<Task>

Promise resolving to the updated task

Throws

If the task is not found

Example

// Update task status to 'completed'
const task = await taskManager.updateTaskStatus('task-123', 'completed');
console.log('Task status updated:', task.status);