🚀 The fast, Pythonic way to build MCP servers and clients. https://gofastmcp.com
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William Easton 7ef5a14d6b
Add doc example validation test (syntax + import checks)
Uses pytest-examples to extract 1,448 Python code blocks from
docs/*.mdx and checks:
- Syntax: every example parses as valid Python
- Imports: every `from fastmcp.x import y` resolves

Current baseline (26 known failures):
- 8 syntax errors (error output as python, unquoted URLs, f-string backticks)
- 18 broken imports (renamed classes, wrong module paths, removed features)

Baselines ratchet down as doc examples are fixed.

🤖 Generated with Claude Code

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-04-12 09:49:48 -05:00
.claude Add review-pr skill for Codex bot workflow (#3552) 2026-03-18 15:30:29 -04:00
.cursor/rules Add agent skills for testing and code review (#2846) 2026-01-12 11:24:39 -05:00
.github Add real-world schema crash test against APIs.guru directory (#3826) 2026-04-11 11:23:55 -04:00
docs Document session state isolation across mount boundaries (#3801) 2026-04-09 16:15:57 -04:00
examples chore(deps): bump the uv group across 2 directories with 1 update (#3795) 2026-04-08 20:08:26 -04:00
scripts Fix auto-close MRE script posting comment without closing (#3386) 2026-03-04 16:56:29 -05:00
skills/fastmcp-client-cli Add fastmcp discover and name-based server resolution (#3055) 2026-02-01 21:27:22 -05:00
src/fastmcp Stop forwarding inbound HTTP headers to unrelated remote servers (#3837) 2026-04-11 12:14:38 -04:00
tests Add doc example validation test (syntax + import checks) 2026-04-12 09:49:48 -05:00
v3-notes docs: fix stale get_* references, now list_* (#3168) 2026-02-12 13:45:49 -06:00
.ccignore Update .ccignore 2025-06-30 18:41:04 -04:00
.coderabbit.yaml Exclude auto-generated python-sdk docs from CodeRabbit reviews (#3206) 2026-02-17 18:28:20 -05:00
.gitignore chore: gitignore .claude/worktrees/ (#3529) 2026-03-16 14:50:15 -04:00
.pre-commit-config.yaml Add loq file size limits and clean up type ignores (#2859) 2026-01-13 07:29:12 -05:00
.python-version Initial commit 2024-11-29 16:42:40 -05:00
AGENTS.md reverse CLAUDE.md/AGENTS.md symlink direction (#3294) 2026-02-25 11:18:59 -05:00
CLAUDE.md Note generate-notes API in release workflow docs (#3806) 2026-04-09 18:08:57 -04:00
CODE_OF_CONDUCT.md Create CODE_OF_CONDUCT.md (#1523) 2025-08-16 16:28:15 -04:00
CONTRIBUTING.md docs: improve contributor guidelines for framework contributions (#3653) 2026-03-27 10:43:12 -04:00
justfile chore: split SDK navigation into standalone $ref file (#3773) 2026-04-06 11:18:14 -04:00
LICENSE Basic cleanup 2025-04-05 17:39:51 -04:00
logo.py Update CLI logo (#2220) 2025-10-22 21:29:04 -04:00
loq.toml Add too-long label to Marvin triage workflow (#3508) 2026-03-14 16:48:33 -04:00
pyproject.toml Add doc example validation test (syntax + import checks) 2026-04-12 09:49:48 -05:00
README.md Sync README with welcome.mdx, fix install count (#3224) 2026-02-18 18:38:20 -05:00
SECURITY.md Update security policy (#3521) 2026-03-15 14:12:17 -04:00
uv.lock Add doc example validation test (syntax + import checks) 2026-04-12 09:49:48 -05:00

FastMCP Logo

FastMCP 🚀

Move fast and make things.

Made with 💙 by Prefect

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prefecthq%2Ffastmcp | Trendshift


The Model Context Protocol (MCP) connects LLMs to tools and data. FastMCP gives you everything you need to go from prototype to production:

from fastmcp import FastMCP

mcp = FastMCP("Demo 🚀")

@mcp.tool
def add(a: int, b: int) -> int:
    """Add two numbers"""
    return a + b

if __name__ == "__main__":
    mcp.run()

Why FastMCP

Building an effective MCP application is harder than it looks. FastMCP handles all of it. Declare a tool with a Python function, and the schema, validation, and documentation are generated automatically. Connect to a server with a URL, and transport negotiation, authentication, and protocol lifecycle are managed for you. You focus on your logic, and the MCP part just works: with FastMCP, best practices are built in.

That's why FastMCP is the standard framework for working with MCP. FastMCP 1.0 was incorporated into the official MCP Python SDK in 2024. Today, the actively maintained standalone project is downloaded a million times a day, and some version of FastMCP powers 70% of MCP servers across all languages.

FastMCP has three pillars:

Servers
Servers

Expose tools, resources, and prompts to LLMs.
Apps
Apps

Give your tools interactive UIs rendered directly in the conversation.
Clients
Clients

Connect to any MCP server — local or remote, programmatic or CLI.

Servers wrap your Python functions into MCP-compliant tools, resources, and prompts. Clients connect to any server with full protocol support. And Apps give your tools interactive UIs rendered directly in the conversation.

Ready to build? Start with the installation guide or jump straight to the quickstart. When you're ready to deploy, Prefect Horizon offers free hosting for FastMCP users.

Installation

We recommend installing FastMCP with uv:

uv pip install fastmcp

For full installation instructions, including verification and upgrading, see the Installation Guide.

Upgrading? We have guides for:

📚 Documentation

FastMCP's complete documentation is available at gofastmcp.com, including detailed guides, API references, and advanced patterns.

Documentation is also available in llms.txt format, which is a simple markdown standard that LLMs can consume easily:

  • llms.txt is essentially a sitemap, listing all the pages in the documentation.
  • llms-full.txt contains the entire documentation. Note this may exceed the context window of your LLM.

Community: Join our Discord server to connect with other FastMCP developers and share what you're building.

Contributing

We welcome contributions! See the Contributing Guide for setup instructions, testing requirements, and PR guidelines.