fast-agent

Overview

Fast-agent is a flexible Python framework designed for interacting with LLMs and building sophisticated agents. It provides comprehensive MCP (Model Context Protocol) support including tools, resources, and elicitations. The framework allows developers to create, chain, and evaluate agents with multiple model providers, interactive shells, and advanced features like MAKER for error reduction in multi-step tasks.

Try asking AI

After installing, here are 5 things you can ask your AI assistant:

• url_fetcher

  Given a URL, provide a complete and comprehensive summary

  Try:Summarize the content of this webpageTry:Fetch and summarize information from this URL
• social_media

  Write a 280 character social media post for any given text

  Try:Create a social media post about this articleTry:Write a short tweet based on this summary
• NY-Project-Manager

  Return NY time + timezone, plus a one-line project status

  Try:What's the current time and project status in New York?Try:Get NY timezone and project information
• London-Project-Manager

  Return London time + timezone, plus a one-line news update

  Try:What's the current time and news update in London?Try:Get London timezone and news information
• classifier

  Reply with only: A, B, or C

  Try:Classify this item as A, B, or CTry:Categorize this input with A, B, or C
• reliable_classifier

  Reliably classify input using sampling with k-voting error reduction

  Try:Reliably classify this as A, B, or CTry:Get a reliable classification with error reduction

Note: Tools are inferred from example code snippets showing agent definitions with MCP server integration. No explicit MCP tools section is documented in the README.

Comparable tools

Installation

# Using uv package manager
uv tool install fast-agent-mcp

# Start an interactive session
fast-agent go -x

# Run as an MCP server
fast-agent go --transport http --port 8001

{
  "mcpServers": {
    "fast-agent": {
      "command": "uv",
      "args": ["run", "fast-agent", "go", "--transport", "stdio"],
      "env": {}
    }
  }
}

FAQ

What is the difference between MCP and ACP in fast-agent?

MCP (Model Context Protocol) is the protocol for connecting to servers, while ACP (Agent Context Protocol) is fast-agent's internal framework for coordinating agents. Fast-agent can serve as either an MCP server or an ACP client.

How do I connect to external MCP servers?

Use the `/connect` command in the interactive shell, e.g. `/connect @modelcontextprotocol/server-everything` or `/connect https://huggingface.co/mcp`. Supports both stdio and HTTP transports.

On Hacker News

Recent discussion from the developer community.

• Show HN: Fast-agent – Compose MCP enabled Agents and Workflows in minutes▲ 29💬 3
  Story by evalstate · 2025-03-06

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