Fastmcp Server

What it does

When your agent uses it

• Creating Python MCP servers
• Integrating AI models with external tools and data

Example prompts

• “/fastmcp-server”

Requirements

• Python 3

What it can do on your machine

Read from SKILL.md and the folder at commit 46b4d8b. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are python).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Fastmcp Server loads about 1.9k tokens when it runs, and up to ~112k if it reads all its reference files. Until then it costs about 60 tokens; SKILL.md has 595 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~60

When it runs · the whole SKILL.md, loaded when a task matches

~1.9k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~112k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from davila7/claude-code-templates at commit 46b4d8b, republished under its MIT licence (© davila7). 595 words, ~1,907 tokens.

name

fastmcp-server

description

Complete guide for building MCP servers with FastMCP 3.0 - tools, resources, authentication, providers, middleware, and deployment. Use when creating Python MCP servers or integrating AI models with external tools and data.

version

1.0.0

author

FastMCP Community

license

MIT

tags

FastMCP, MCP, Python, AI, Tools, Server, Authentication, Providers

from fastmcp import FastMCP

mcp = FastMCP("MyServer")

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

@mcp.resource("data://config")
def get_config() -> dict:
    """Return server configuration"""
    return {"version": "1.0", "debug": False}

@mcp.resource("users://{user_id}/profile")
def get_user_profile(user_id: str) -> dict:
    """Get a user's profile by ID"""
    return fetch_user(user_id)

@mcp.prompt
def review_code(code: str, language: str = "python") -> str:
    """Review code for best practices"""
    return f"Review this {language} code:\n\n{code}"

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

# Or with transport options:
# mcp.run(transport="sse", host="0.0.0.0", port=8000)

from fastmcp import FastMCP, Context

mcp = FastMCP("MyServer")

@mcp.tool
def process_data(uri: str, ctx: Context) -> str:
    """Process data with logging and progress"""
    ctx.info(f"Processing {uri}")
    ctx.report_progress(0, 100)
    data = ctx.read_resource(uri)
    ctx.report_progress(100, 100)
    return f"Processed: {data}"

from fastmcp import FastMCP
from fastmcp.server.auth import BearerAuthProvider

auth = BearerAuthProvider(
    jwks_uri="https://your-provider/.well-known/jwks.json",
    audience="your-api",
    issuer="https://your-provider/"
)

mcp = FastMCP("SecureServer", auth=auth)

© davila7, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 33 other files (references) in cli-tool/components/skills/development/fastmcp-server of davila7/claude-code-templates.

• SKILL.md
• references/authentication/full-oauth-server.md
• references/authentication/oauth-proxy.md
• references/authentication/oidc-proxy.md
• references/authentication/remote-oauth.md
• references/authentication/token-verification.md
• references/authorization.md
• references/context/background-tasks.md
• references/context/dependency-injection.md
• references/context/mcp-context.md
• references/context/user-elicitation.md
• references/features/client-logging.md
• references/features/icons.md
• references/features/lifespans.md
• references/features/middleware.md
• references/features/opentelemetry.md
• references/features/pagination.md
• … and 17 more

Open the folder on GitHubat commit 46b4d8b