Filesystem MCP Server

Ruby server implementing Model Context Protocol (MCP) for filesystem operations using the vector_mcp gem.

Features

• Read/write files
• Create/list/delete directories
• Move files/directories
• Search files
• Get file metadata

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

API

Resources

• file://system: File system operations interface

Tools

• read_file

  • Read complete contents of a file
  • Input: path (string)
  • Reads complete file contents with UTF-8 encoding

• read_multiple_files

  • Read multiple files simultaneously
  • Input: paths (string[])
  • Failed reads won't stop the entire operation

• write_file

  • Create new file or overwrite existing (exercise caution with this)
  • Inputs:
    • path (string): File location
    • content (string): File content

• edit_file

  • Make exact text (substring) replacements in a file.
  • Features:
    • Line-based and multi-line content matching
    • Multiple simultaneous edits with correct positioning
    • Git-style diff output with context
    • Preview changes with dry run mode
  • Inputs:
    • path (string): File to edit
    • edits (array): List of edit operations
      • oldText (string): Text to search for (can be substring)
      • newText (string): Text to replace with
    • dryRun (boolean): Preview changes without applying (default: false)
  • Returns detailed diff and match information for dry runs, otherwise applies changes
  • Best Practice: Always use dryRun first to preview changes before applying them

• create_directory

  • Create new directory or ensure it exists
  • Input: path (string)
  • Creates parent directories if needed
  • Succeeds silently if directory exists

• list_directory

  • List directory contents as a JSON array, with each item containing 'name' and 'type' ('file' or 'directory').
  • Input: path (string)

• move_file

  • Move or rename files and directories
  • Inputs:
    • source (string)
    • destination (string)
  • Fails if destination exists

• search_files

  • Recursively search for files/directories
  • Inputs:
    • path (string): Starting directory
    • pattern (string): Search pattern
    • excludePatterns (string[]): Exclude any patterns. Glob formats are supported.
  • Case-insensitive matching
  • Returns full paths to matches

• get_file_info

  • Get detailed file/directory metadata
  • Input: path (string)
  • Returns:
    • Size
    • Creation time
    • Modified time
    • Access time
    • Type (file/directory)
    • Permissions

• list_allowed_directories

  • List all directories the server is allowed to access
  • No input required
  • Returns:
    • Directories that this server can read/write from

Usage with Claude Desktop

Add this to your claude_desktop_config.json:

{
  "mcpServers": {
    "filesystem": {
      "command": "ruby",
      "args": [
        "/Users/your_username/file_system_mcp/file_system_mcp.rb",
        "/Users/your_username/Desktop",
        "/path/to/other/allowed/dir"
      ]
    }
  }
}

About the args array

1. The first element is the absolute path to the file_system_mcp.rb script.
2. Every subsequent element is an absolute path to a directory that the server is allowed to read from and write to.

Make sure to replace all of these paths with locations that exist on your machine before starting Claude Desktop.