FastMCP Server — Minimal Docker Example

A minimal FastMCP server deployable with Docker, compatible with Claude Code and GitHub Copilot (VS Code).

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Project Structure

.
├── server.py          # FastMCP server (stdio transport)
├── server_http.py     # FastMCP server (HTTP transport)
├── Dockerfile         # For stdio transport (Claude Code via docker run -i)
├── Dockerfile.http    # For HTTP transport (remote / compose)
├── docker-compose.yml # Starts HTTP server on port 8000
└── .vscode/
    └── mcp.json       # GitHub Copilot MCP configuration

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Transport Methods

MCP supports two transport modes — choose based on your use case:

Transport	Use case	Config
stdio	Local Docker container spawned per session	docker run -i --rm <image>
HTTP	Remote server, shared across clients	http://localhost:8000/mcp

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Option A — stdio Transport (Claude Code)

Best for local dev. Claude Code spawns the container and communicates via stdin/stdout.

1. Build the image

docker build -t fastmcp-demo .

2. Register with Claude Code

claude mcp add demo-server -- docker run -i --rm fastmcp-demo

2.1 Verify

claude mcp list
# Then inside a Claude Code session:
/mcp

3. Connect from GitHub Copilot (VS Code)

The .vscode/mcp.json file is already configured. VS Code will auto-discover it. Open VS Code → Command Palette → MCP: List Servers to confirm.

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Option B — HTTP Transport (Claude Code + GitHub Copilot)

Best for team sharing or remote deployment. Run the server once, connect from anywhere.

1. Start with Docker Compose

docker compose up -d
# Server is now at http://localhost:8000/mcp

2. Connect from Claude Code

claude mcp add --transport http demo-server http://localhost:8000/mcp

3. Connect from GitHub Copilot (VS Code)

The .vscode/mcp.json file is already configured. VS Code will auto-discover it. Open VS Code → Command Palette → MCP: List Servers to confirm.

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Adding Your Own Tools

Edit server.py (or server_http.py) and add decorated functions:

@mcp.tool
def my_tool(input: str) -> str:
    """Tool description shown to the LLM."""
    return input.upper()

FastMCP automatically infers the tool name, parameters, and schema from the function signature and docstring.

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Tips

• Secrets: Pass environment variables with -e in docker run or via env: in docker-compose.yml. For Claude Code: claude mcp add -e MY_KEY=value demo -- docker run -i -e MY_KEY --rm fastmcp-demo
• stdio limitation: stdio transport only works when the MCP client (Claude Code) can directly spawn the process. If Claude Code runs inside a container itself, use HTTP transport instead.
• GitHub Copilot: Requires VS Code 1.99+ and the GitHub Copilot extension. HTTP transport is generally more reliable for Copilot.