Cover Letter MCP Server

A Model Context Protocol (MCP) server that generates professional PDF cover letters using LaTeX. This server integrates seamlessly with Claude Desktop to create beautifully formatted cover letters with a clean, professional design and advanced folder management capabilities.

Features

• 🎯 Professional Design: Clean, modern layout matching professional resume standards
• 📄 PDF Generation: High-quality PDF output using LaTeX
• 🔧 Claude Desktop Integration: Works directly within Claude Desktop interface
• 📁 Advanced Folder Management: Create custom folders and organize cover letters by job, company, or category
• 🗂️ Directory Navigation: List and browse your cover letter collection with built-in file explorer
• ⚡ Fast Generation: Dockerized environment for consistent, quick processing
• 🛡️ Input Sanitization: Automatic escaping of special characters for LaTeX safety
• 🔒 Secure Paths: Built-in path sanitization prevents security issues

Prerequisites

• Docker: Make sure Docker Desktop is installed and running
• Claude Desktop: Latest version with MCP support
• Git: For cloning the repository

Quick Start

1. Clone the Repository

git clone https://github.com/YOUR_USERNAME/cover-letter-mcp.git
cd cover-letter-mcp

2. Create Downloads Directory

mkdir downloads

3. Build the Docker Image

docker build -t cover-letter-mcp .

4. Configure Claude Desktop

Add the following configuration to your Claude Desktop config file:

Location of config file:

• Windows: %APPDATA%\Claude\claude_desktop_config.json
• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

Configuration:

{
  "mcpServers": {
    "cover-letter-generator": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "-v",
        "/path/to/your/cover-letter-mcp/downloads:/downloads",
        "cover-letter-mcp",
        "python",
        "server.py"
      ]
    }
  }
}

**Replace /path/to/your/cover-letter-mcp/downloads with your actual path:**

• Windows: "C:/Users/YourUsername/path/to/cover-letter-mcp/downloads:/downloads"
• macOS/Linux: "/Users/YourUsername/path/to/cover-letter-mcp/downloads:/downloads"

5. Restart Claude Desktop

Restart Claude Desktop to load the new MCP server configuration.

Usage

Once configured, you can generate cover letters directly in Claude Desktop with advanced organization features:

Example Usage

Basic Cover Letter Generation

Generate a cover letter for:
- Name: John Smith
- Company: Tech Innovations Inc
- Position: Software Engineer
- Body: I am writing to express my interest in the Software Engineer position at your company. With 5 years of experience in software development, I believe I would be a great fit for your team. My skills in JavaScript and Python align well with your requirements. I look forward to discussing this opportunity further.

Organized Cover Letter with Custom Folder

Generate a cover letter for Jane Doe applying to Google for a Senior Developer position and save it in the "FAANG-applications/google" folder

Advanced Organization

Create a cover letter for the Product Manager role at Netflix. Save it in "streaming-companies/netflix" with filename "pm-application-2024"

Folder Management

Create a folder structure for organizing my job applications: "job-search-2024/tech-companies" and "job-search-2024/startups"

Show me what cover letters I have in my "tech-companies" folder

Smart Organization Features

• 🗂️ Auto-Folder Creation - Folders are created automatically when generating cover letters
• 📁 Custom Directory Structure - Organize by company, role type, industry, or any system that works for you
• 🔍 Directory Browser - List contents of any folder to see your cover letter collection
• 📊 File Information - View file sizes, creation dates, and organize by metadata
• 🛡️ Path Security - Built-in sanitization prevents directory traversal and invalid characters

Organization Examples

By Company:

• applications/google/
• applications/microsoft/
• applications/amazon/

By Role Type:

• roles/software-engineer/
• roles/product-manager/
• roles/data-scientist/

By Industry:

• industries/fintech/
• industries/healthcare/
• industries/gaming/

By Status:

• drafts/
• submitted/2024/
• archived/old-versions/

Advanced Options

Custom filename with organization:

Generate a cover letter with filename "tech_innovations_application" for John Smith applying to Tech Innovations Inc and save it in the "applications/tech-startups" folder

Multiple applications organization:

I'm applying to several FAANG companies. Create cover letters for:
1. Google - Software Engineer role (save in "faang/google")
2. Meta - Frontend Developer role (save in "faang/meta")
3. Amazon - Backend Engineer role (save in "faang/amazon")

API Reference

Tools Available

generate_cover_letter

Generates a PDF cover letter from structured data with optional folder organization.

Parameters:

• name (string): Full name of the applicant
• company (string): Company name
• position (string): Position being applied for
• body (string): Main body text of the cover letter
• filename (string, optional): Custom filename (without .pdf extension)
• folderPath (string, optional): Custom folder path within downloads directory

Example:

{
  "name": "John Smith",
  "company": "Tech Corp",
  "position": "Software Engineer",
  "body": "I am writing to express my strong interest...",
  "filename": "john-smith-tech-corp-application",
  "folderPath": "job-applications/tech-companies/tech-corp"
}

create_folder

Creates a new folder within the downloads directory.

Parameters:

• folderPath (string): Folder path to create (supports nested folders)

Example:

{
  "folderPath": "applications/2024/q1"
}

list_folders

Lists all folders and files in the downloads directory.

Parameters:

• path (string, optional): Specific subdirectory to list

Example:

{
  "path": "applications/tech-companies"
}

File Structure

cover-letter-mcp/
├── server.py              # Main MCP server with folder management
├── Dockerfile             # Docker container configuration
├── requirements.txt       # Python dependencies
├── downloads/             # Generated PDFs organized in folders
│   ├── applications/
│   │   ├── google/
│   │   │   ├── john-smith-swe-2024.pdf
│   │   │   └── jane-doe-pm-2024.pdf
│   │   ├── microsoft/
│   │   └── startups/
│   ├── drafts/
│   └── templates/
└── README.md             # This file

Technical Details

LaTeX Template

The server uses a custom LaTeX template that creates:

• Clean, centered header with applicant name
• Professional spacing and typography
• Automatic date insertion
• Proper business letter formatting
• High-quality PDF output

Security Features

• Input Sanitization: All user input is properly escaped for LaTeX
• Filename Safety: Generated filenames are sanitized to prevent path traversal
• Path Security: Folder paths are sanitized to prevent directory traversal attacks
• Isolated Environment: Docker container provides secure, isolated execution
• Character Filtering: Removes or replaces invalid filesystem characters

MCP Protocol

This server implements the Model Context Protocol specification:

• Tools: generate_cover_letter, create_folder, list_folders
• Resources: Lists and provides access to generated PDFs (including nested folders)
• Capabilities: Full read/write access to cover letter generation and folder management

Troubleshooting

Common Issues

"Docker command not found"

• Ensure Docker Desktop is installed and running
• Verify Docker is in your system PATH

"Permission denied" on Windows

• Make sure Docker Desktop has access to your drive
• Try running PowerShell as Administrator
• Ensure the downloads folder has write permissions

"Container not found"

• Rebuild the Docker image: docker build -t cover-letter-mcp .
• Check that the image name matches your configuration

"LaTeX compilation failed"

• This usually indicates special characters in the input
• The server automatically escapes most characters, but some complex formatting may need adjustment

"Folder creation errors"

• Verify write permissions in the downloads directory
• Check that folder paths don't contain invalid characters
• Ensure Docker has access to the mounted volume

"Path-related issues"

• Folder paths are automatically sanitized for security
• Invalid characters are replaced with underscores
• Directory traversal attempts (../) are automatically blocked

Debug Mode

To see detailed logs from the MCP server, check the Claude Desktop developer console or run the Docker container manually:

docker run --rm -i -v "./downloads:/downloads" cover-letter-mcp python server.py

For verbose debugging:

docker run --rm -i -v "./downloads:/downloads" -e DEBUG=1 cover-letter-mcp python server.py

Development

Local Development

For development without Docker:

1. Install Python dependencies:

pip install -r requirements.txt

2. Install LaTeX (varies by system):

# Ubuntu/Debian
   sudo apt-get install texlive-latex-base texlive-latex-recommended

   # macOS with Homebrew
   brew install --cask mactex

   # Windows
   # Download and install MiKTeX or TeX Live

3. Run the server:

python server.py

Security Considerations

• Path Validation: All folder paths are validated and sanitized
• Input Escaping: LaTeX special characters are properly escaped
• Container Isolation: Docker provides process and filesystem isolation
• Volume Mounting: Only the downloads directory is accessible to the container

Contributing

1. Fork the repository

2. Create a feature branch: git checkout -b feature-name

3. Make your changes

4. Test thoroughly with various folder structures

5. Submit a pull request

License

MIT License - see LICENSE file for details.

Support

If you encounter issues:

1. Check the troubleshooting section

2. Review the Claude Desktop MCP documentation

3. Open an issue on GitHub with:

• Your operating system
• Claude Desktop version
• Docker version
• Complete error messages
• Steps to reproduce

Changelog

v2.0.0 - Folder Management Update

• ✨ NEW: Custom folder organization within downloads directory
• ✨ NEW: create_folder tool for creating organized directory structures
• ✨ NEW: list_folders tool for browsing and managing cover letter collections
• ✨ NEW: Enhanced generate_cover_letter with folderPath parameter
• 🛡️ NEW: Path sanitization and security features
• 📊 NEW: File metadata display (size, date) in directory listings
• 🗂️ NEW: Auto-creation of folder paths when generating cover letters
• 📁 NEW: Support for nested folder structures
• 🔍 NEW: Directory navigation and file organization tools
• 🔒 NEW: Enhanced security with Docker volume isolation

v1.0.0

• Initial release
• Professional LaTeX cover letter generation
• Docker containerization
• Claude Desktop integration
• Basic PDF output to downloads folder

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Made with ❤️ for the Claude Desktop and MCP community