servers

Filesystem MCP Server

Node.js server implementing Model Context Protocol (MCP) for filesystem operations.

Features

Directory Access Control

The server uses a flexible directory access control system. Directories can be specified via command-line arguments or dynamically via Roots.

Method 1: Command-line Arguments

Specify Allowed directories when starting the server:

mcp-server-filesystem /path/to/dir1 /path/to/dir2

MCP clients that support Roots can dynamically update the Allowed directories.

Roots notified by Client to Server, completely replace any server-side Allowed directories when provided.

Important: If server starts without command-line arguments AND client doesn’t support roots protocol (or provides empty roots), the server will throw an error during initialization.

This is the recommended method, as this enables runtime directory updates via roots/list_changed notifications without server restart, providing a more flexible and modern integration experience.

How It Works

The server’s directory access control follows this flow:

  1. Server Startup
    • Server starts with directories from command-line arguments (if provided)
    • If no arguments provided, server starts with empty allowed directories
  2. Client Connection & Initialization
    • Client connects and sends initialize request with capabilities
    • Server checks if client supports roots protocol (capabilities.roots)
  3. Roots Protocol Handling (if client supports roots)
    • On initialization: Server requests roots from client via roots/list
    • Client responds with its configured roots
    • Server replaces ALL allowed directories with client’s roots
    • On runtime updates: Client can send notifications/roots/list_changed
    • Server requests updated roots and replaces allowed directories again
  4. Fallback Behavior (if client doesn’t support roots)
    • Server continues using command-line directories only
    • No dynamic updates possible
  5. Access Control
    • All filesystem operations are restricted to allowed directories
    • Use list_allowed_directories tool to see current directories
    • Server requires at least ONE allowed directory to operate

Note: The server will only allow operations within directories specified either via args or via Roots.

API

Tools

Tool annotations (MCP hints)

This server sets MCP ToolAnnotations on each tool so clients can:

The mapping for filesystem tools is:

Tool readOnlyHint idempotentHint destructiveHint Notes
read_text_file true Pure read
read_media_file true Pure read
read_multiple_files true Pure read
list_directory true Pure read
list_directory_with_sizes true Pure read
directory_tree true Pure read
search_files true Pure read
get_file_info true Pure read
list_allowed_directories true Pure read
create_directory false true false Re‑creating the same dir is a no‑op
write_file false true true Overwrites existing files
edit_file false false true Re‑applying edits can fail or double‑apply
move_file false false true Deletes source file

Note: idempotentHint and destructiveHint are meaningful only when readOnlyHint is false, as defined by the MCP spec.

Usage with Claude Desktop

Add this to your claude_desktop_config.json:

Note: you can provide sandboxed directories to the server by mounting them to /projects. Adding the ro flag will make the directory readonly by the server.

Docker

Note: all directories must be mounted to /projects by default.

{
  "mcpServers": {
    "filesystem": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "--mount", "type=bind,src=/Users/username/Desktop,dst=/projects/Desktop",
        "--mount", "type=bind,src=/path/to/other/allowed/dir,dst=/projects/other/allowed/dir,ro",
        "--mount", "type=bind,src=/path/to/file.txt,dst=/projects/path/to/file.txt",
        "mcp/filesystem",
        "/projects"
      ]
    }
  }
}

NPX

{
  "mcpServers": {
    "filesystem": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-filesystem",
        "/Users/username/Desktop",
        "/path/to/other/allowed/dir"
      ]
    }
  }
}

Usage with VS Code

For quick installation, click the installation buttons below…

Install with NPX in VS Code Install with NPX in VS Code Insiders

Install with Docker in VS Code Install with Docker in VS Code Insiders

For manual installation, you can configure the MCP server using one of these methods:

Method 1: User Configuration (Recommended) Add the configuration to your user-level MCP configuration file. Open the Command Palette (Ctrl + Shift + P) and run MCP: Open User Configuration. This will open your user mcp.json file where you can add the server configuration.

Method 2: Workspace Configuration Alternatively, you can add the configuration to a file called .vscode/mcp.json in your workspace. This will allow you to share the configuration with others.

For more details about MCP configuration in VS Code, see the official VS Code MCP documentation.

You can provide sandboxed directories to the server by mounting them to /projects. Adding the ro flag will make the directory readonly by the server.

Docker

Note: all directories must be mounted to /projects by default.

{
  "servers": {
    "filesystem": {
      "command": "docker",
      "args": [
        "run",
        "-i",
        "--rm",
        "--mount", "type=bind,src=${workspaceFolder},dst=/projects/workspace",
        "mcp/filesystem",
        "/projects"
      ]
    }
  }
}

NPX

{
  "servers": {
    "filesystem": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-filesystem",
        "${workspaceFolder}"
      ]
    }
  }
}

Build

Docker build:

docker build -t mcp/filesystem -f src/filesystem/Dockerfile .

License

This MCP server is licensed under the MIT License. This means you are free to use, modify, and distribute the software, subject to the terms and conditions of the MIT License. For more details, please see the LICENSE file in the project repository.