🔍 Nexus MCP Server

AI integration without the complexity

Intelligent AI model search and discovery with zero-install simplicity

Quick Start • Features • Documentation • Contributing

🚀 What is Nexus?

Nexus is a production-ready Model Context Protocol (MCP) server that brings AI-powered web search directly into your development environment. Get intelligent search results with proper citations in Claude Desktop, Cursor, or any MCP-compatible client - all with a single command.

Why Nexus?

• 🎯 Zero Setup: Ready in 30 seconds with npx - no installation, no configuration

• 🧠 AI-Powered: Uses Perplexity Sonar models for intelligent, current web search

• 📚 Source Citations: Get authoritative sources with every search result

• 🔧 Developer-First: Built for developers who want AI capabilities without complexity

• ⚡ Production-Ready: Enterprise-grade reliability with comprehensive error handling

✨ Features

🚀 Zero-Install Simplicity

• Ready in 30 seconds with npx

• No dependencies or build steps

• Cross-platform compatibility

• Always up-to-date

🧠 AI-Powered Intelligence

• Perplexity Sonar model integration

• Real-time web content search

• Context-aware result ranking

• Multiple model options

📚 Professional Quality

• Source citations and metadata

• Comprehensive error handling

• Production-grade reliability

• TypeScript implementation

🔧 Developer Experience

• MCP protocol compliance

• Extensive documentation

• Configurable parameters

• Community support

🏃‍♂️ Quick Start

🚀 Zero-install setup - Ready in 30 seconds!

Prerequisites

• Node.js 16 or higher

• An OpenRouter API key (get one at OpenRouter)

Zero-Config Installation

No build steps, no dependencies, no setup required:

That's it! The server is now running and ready for MCP client connections.

Testing the NPX Installation

Alternative: Local Development Installation

For local development or customization:

1. Clone the repository:

2. Install dependencies:

3. Build the server:

4. Configure your OpenRouter API key:

5. Test the server:

Integration with MCP Clients

🚀 Quick Setup with NPX (Recommended)

The easiest way to integrate with any MCP client is using NPX:

Claude Code

Add this server to your Claude Code MCP settings:

1. Open your MCP settings file (usually ~/.claude/mcp_settings.json)

2. Add the server configuration using NPX:

3. Restart Claude Code

That's it! No installation, no build steps, no path configuration required.

Cursor

Configure the server in Cursor's MCP settings:

1. Open Cursor settings and navigate to MCP servers

2. Add a new server with:

   • Name: nexus

   • Command: npx

   • Args: ["nexus-mcp"]

   • Environment Variables:

     • OPENROUTER_API_KEY: your-api-key-here

3. Restart Cursor

Other MCP Clients

For any MCP-compatible client, use these connection details:

• Transport: stdio

• Command: npx

• Args: ["nexus-mcp"]

• Environment Variables: OPENROUTER_API_KEY=your-api-key-here

Alternative: Local Installation

If you prefer using a local installation (after following the local development setup):

Usage

Once integrated, you can use the search tool in your MCP client:

Basic Search

Advanced Search with Parameters

Available Tools

search

The main search tool that provides AI-powered web search capabilities.

Parameters:

• query (required): Search query (1-2000 characters)

• model (optional): Perplexity model to use (default: "perplexity/sonar")

• maxTokens (optional): Maximum response tokens (1-4000, default: 1000)

• temperature (optional): Response randomness (0-2, default: 0.7)

Example Response:

Configuration

Environment Variables

• OPENROUTER_API_KEY (required): Your OpenRouter API key

• NODE_ENV (optional): Environment setting (development, production, test)

• LOG_LEVEL (optional): Logging level (debug, info, warn, error)

Advanced Configuration

The server supports additional configuration through environment variables:

• OPENROUTER_TIMEOUT_MS: Request timeout in milliseconds (default: 30000)

• OPENROUTER_MAX_RETRIES: Maximum retry attempts (default: 3)

• OPENROUTER_BASE_URL: Custom OpenRouter API base URL

Resources

The server provides a configuration status resource at config://status that shows:

• Server health status

• Configuration information (with masked API key)

• Search tool availability

• Server uptime and version

Troubleshooting

NPX-Specific Issues

"npx: command not found"

• Ensure Node.js 16+ is installed: node --version

• Update npm: npm install -g npm@latest

"Cannot find package 'nexus-mcp'"

• The package may not be published yet. Use local installation instead

• Verify network connectivity for npm registry access

NPX takes a long time to start

• This is normal on first run as NPX downloads the package

• Subsequent runs will be faster due to caching

• For faster startup, use local installation instead

"Permission denied" errors with NPX

• Try: npx --yes nexus-mcp --stdio

• Or set npm permissions: npm config set user 0 && npm config set unsafe-perm true

Common Issues

"Search functionality is not available"

• Ensure OPENROUTER_API_KEY environment variable is set

• Verify your API key is valid at OpenRouter

• Check the server logs for initialization errors

"Authentication failed: Invalid API key"

• Double-check your API key format and validity

• Ensure the key has sufficient credits/permissions

• Test the key directly at OpenRouter dashboard

"Rate limit exceeded"

• Wait for the rate limit to reset (usually 1 minute)

• Consider upgrading your OpenRouter plan for higher limits

• Monitor usage in your OpenRouter dashboard

Connection timeouts

• Check your internet connection

• The server will automatically retry failed requests

• Increase timeout if needed: OPENROUTER_TIMEOUT_MS=60000

MCP client can't connect to server

• Verify your MCP configuration uses the correct command and arguments

• Check that Node.js 16+ is available in your MCP client's environment

• Ensure the API key is properly set in the environment variables

Debug Logging

Enable debug logging by:

For local development: Add LOG_LEVEL=debug to your .env file

For MCP clients: Add LOG_LEVEL: "debug" to the env section of your MCP configuration

This will provide detailed information about:

• Configuration loading

• API requests and responses

• Error details and stack traces

• Performance metrics

Testing Connection

You can test if the server is working by checking the configuration status resource in your MCP client, or by running a simple search query.

Development

For developers working on this server:

💰 API Credits and Costs

This server uses OpenRouter's API, which charges based on token usage:

• Perplexity Sonar models: Check current pricing at OpenRouter Models

• Usage monitoring: Track consumption through the OpenRouter dashboard

• Cost control: Set usage limits in your OpenRouter account

• Optimization: Nexus includes built-in rate limiting and intelligent caching

📚 Documentation

🤝 Contributing

We welcome contributions from developers of all experience levels!

🚀 Get Started

• Fork the repository

• Read our Contributing Guide

• Check out good first issues

🐛 Report Issues

• Bug Reports

• Feature Requests

• Ask Questions

💬 Join Community

• GitHub Discussions

• Code of Conduct

• Roadmap & Project Board

🌟 Recognition

Contributors are recognized in our:

• Contributors list

• Release notes for significant contributions

• Community spotlights and testimonials

🔗 Related Projects

• Model Context Protocol - The standard we implement

• OpenRouter - Our AI model provider

• Claude Desktop - Primary MCP client

• Cursor - AI-powered code editor with MCP support

📞 Support & Community

📄 License

MIT License - see LICENSE file for details.

Made with ❤️ by the open source community

⭐ Star us on GitHub • 📦 View on NPM • 📚 Read the Docs

Nexus: AI integration without the complexity