Async Applications with Agents

This example demonstrates how to use a CodeAgent from the smolagents library in an asynchronous Starlette web application. The agent is executed in a background thread using anyio.to_thread.run_sync, allowing you to integrate synchronous agent logic into an async web server.

Key Concepts

• Starlette: A lightweight ASGI framework for building async web apps.
• anyio.to_thread.run_sync: Runs blocking (sync) code in a thread, so it doesn't block the async event loop.
• CodeAgent: An agent from the smolagents library that can be used to solve tasks programmatically.

How it works

• The Starlette app exposes a /run-agent endpoint that accepts a JSON payload with a task string.
• When a request is received, the agent is run in a background thread using anyio.to_thread.run_sync.
• The result is returned as a JSON response.

Implementation Note

Why use a background thread?

CodeAgent.run() executes Python code synchronously, which would block Starlette's async event loop if called directly. By offloading this synchronous operation to a separate thread with anyio.to_thread.run_sync, we maintain the application's responsiveness while the agent processes requests, ensuring optimal performance in high-concurrency scenarios.

Usage

1. Install dependencies:

   bashCopy

   pip install smolagents starlette anyio uvicorn
   

2. Run the app:

   bashCopy

   uvicorn async_codeagent_starlette.main:app --reload
   

3. Test the endpoint:

   bashCopy

   curl -X POST http://localhost:8000/run-agent -H 'Content-Type: application/json' -d '{"task": "What is 2+2?"}'
   

Files

• main.py: Main Starlette application with async endpoint using CodeAgent.
• README.md: This file.

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This example is designed to be clear and didactic for users new to async Python and agent integration.