fastmcp/examples/tasks

FastMCP Tasks Example

Demonstrates background task execution with Docket, including progress tracking, distributed backends, and CLI worker management.

Setup

# From the fastmcp root directory
uv sync

# Start Redis
cd examples/tasks
docker compose up -d

# Load environment (or source .envrc manually)
direnv allow

# Run the server
fastmcp run server.py

For single-process mode without Redis, set FASTMCP_DOCKET_URL=memory:// (note: CLI workers won't work).

Running the Client

# Background execution with progress callbacks
python examples/tasks/client.py --duration 10

# Immediate execution (blocks)
python examples/tasks/client.py immediate --duration 5

Starting Additional Workers

With Redis, you can run additional workers to process tasks in parallel:

fastmcp tasks worker server.py

# Configure via environment:
export FASTMCP_DOCKET_CONCURRENCY=20
fastmcp tasks worker server.py

Backend options:

• memory:// - Single-process only (default)
• redis:// - Distributed, multi-process (Redis or Valkey)

Environment Variables

Variable	Default	Description
FASTMCP_ENABLE_TASKS	false	Enable MCP task protocol (SEP-1686)
FASTMCP_DOCKET_URL	memory://	Docket backend URL

Learn More

• FastMCP Tasks Documentation
• Docket Documentation
• MCP Task Protocol (SEP-1686)