"""FastMCP server entry point for paper download MCP server."""
import os
from mcp.server.fastmcp import FastMCP
# Initialize FastMCP server
mcp = FastMCP("paper-download-mcp")
# Global configuration
EMAIL = os.getenv("PAPER_DOWNLOAD_EMAIL")
DEFAULT_OUTPUT_DIR = os.getenv("PAPER_DOWNLOAD_OUTPUT_DIR", "./downloads")
def _require_email() -> str:
"""
Validate that email configuration is present.
Returns:
Email address
Raises:
ValueError: If PAPER_DOWNLOAD_EMAIL environment variable is not set
"""
if not EMAIL:
raise ValueError(
"PAPER_DOWNLOAD_EMAIL environment variable is required.\n"
"This email is used for Unpaywall API compliance.\n\n"
"To configure:\n"
"1. Set environment variable: export PAPER_DOWNLOAD_EMAIL=your-email@university.edu\n"
"2. Or add to Claude Desktop config:\n"
" {\n"
' "mcpServers": {\n'
' "paper-download": {\n'
' "command": "uvx",\n'
' "args": ["paper-download-mcp"],\n'
' "env": {"PAPER_DOWNLOAD_EMAIL": "your-email@university.edu"}\n'
" }\n"
" }\n"
" }\n"
)
return EMAIL
def main():
"""Main entry point for the MCP server."""
# Validate email configuration on startup
_require_email()
# Import tools to register them with the server
# Must import before mcp.run() to ensure tools are registered
from .tools import download, metadata # noqa: F401
# Run the FastMCP server with stdio transport
mcp.run(transport="stdio")
if __name__ == "__main__":
main()
