MCP Tasks Extension

This repository contains the official Model Context Protocol Tasks extension (io.modelcontextprotocol/tasks), based on SEP-2663.

Why Tasks?

Some MCP requests finish quickly. Others run for minutes, wait for human input, or need to survive a disconnected client. The Tasks extension lets a receiver return a durable task handle so the requester can follow progress and retrieve the result later.

Use Tasks for long computations, approval workflows, external job systems, and call-now/fetch-later APIs.

Extension Identifier: io.modelcontextprotocol/tasks

Use it from TypeScript

The @modelcontextprotocol/ext-tasks package provides generation-agnostic requester lifecycle APIs and 2025-11-25 Tasks receiver support. Start with the TypeScript package guide or call your first task-enabled tool.

Schemas

Version	Status	TypeScript	JSON Schema
2026-07-28	Stable	schema.ts	schema.json
draft	Development	schema.ts	schema.json

Released schema directories are immutable snapshots with version-specific JSON Schema identifiers. Development and schema generation target schema/draft/ only. To create a release snapshot from the current draft:

npm run snapshot:schema -- YYYY-MM-DD

Development

SDK Package

The redistributable package lives in packages/ext-tasks and publishes as @modelcontextprotocol/ext-tasks.

# Run schema, package, and packed-consumer checks
npm run check

# Run the package tests in watch mode
npm run test:watch

# Create the publishable tarball
npm run pack:package

The package intentionally has no root export. Consumers import /client, /receiver, /core, /core/v1, or /core/v2; the guide explains which entry point owns each workflow.

Schema Generation

The draft JSON Schema is auto-generated from the TypeScript type definitions using ts-to-zod and Zod's toJSONSchema(). Do not hand-edit schema.json or generated/schema.ts.

# Generate draft Zod schemas and JSON Schema from schema.ts
npm run generate:schemas

# Verify TypeScript compiles and draft generated files are up to date
npm run check:schema

Governance

This repository follows the Model Context Protocol Governance process. See MAINTAINERS.md for the list of maintainers specific to this repository.

Policies

This repository follows the Model Context Protocol project policies:

• Code of Conduct
• Contributing Guidelines
• Security Policy

License

This project is licensed under the Apache License 2.0. See LICENSE for details.