McGravity: Load-Balance Your MCP Servers Like a Pro

If you're running MCP servers in production, you've probably hit the same scaling wall everyone else has: one server per client connection. McGravity changes that by putting a proper load-balancer in front of your MCP infrastructure, just like Nginx does for web servers.

Stop Managing Multiple MCP Connections

Instead of juggling separate connections to each MCP server, McGravity gives you a single endpoint that automatically distributes requests across your fleet. Your applications connect to one URL, and McGravity handles the rest.

Before McGravity:

// Managing connections to multiple MCP servers
const mcpClient1 = new MCPClient('http://mcp-server-1:3001');
const mcpClient2 = new MCPClient('http://mcp-server-2:3001');
const mcpClient3 = new MCPClient('http://mcp-server-3:3001');

// Manual load balancing logic
const server = getRandomServer([mcpClient1, mcpClient2, mcpClient3]);

With McGravity:

// Single connection, automatic load balancing
const mcpClient = new MCPClient('http://mcgravity-proxy:3001');

Key Benefits for Production MCP Deployments

• Horizontal Scaling: Add more MCP servers without changing client code
• High Availability: Automatic failover when servers go down
• Load Distribution: Weighted round-robin balancing across your server pool
• Health Monitoring: Built-in health checks with /health endpoint
• Zero-Config Docker: Available on Docker Hub with sensible defaults

Real-World Use Cases

API Gateway for MCP Services: Route requests from your web app to a pool of specialized MCP servers, each handling different capabilities (file operations, database queries, external APIs).

Development Environment: Run multiple versions of your MCP server for A/B testing while keeping your client applications unchanged.

Production Scaling: Start with one MCP server, then add capacity by spinning up additional instances behind McGravity without touching your application code.

Quick Setup

Install globally:

npm install -g mcgravity

Create a config file:

# mcgravity.yaml
servers:
  - url: http://mcp-server-1:3001
    weight: 2
  - url: http://mcp-server-2:3001
    weight: 1
  - url: http://mcp-server-3:3001
    weight: 1

Start the proxy:

mcgravity --config mcgravity.yaml --port 8080

That's it. Your applications can now connect to http://localhost:8080 and McGravity will distribute requests across all three servers with the specified weights.

Docker-First Approach

McGravity is designed for containerized deployments:

docker run -p 8080:8080 \
  -v $(pwd)/mcgravity.yaml:/app/config.yaml \
  tigranbs/mcgravity --config /app/config.yaml

Or use environment variables for simpler setups:

docker run -p 8080:8080 \
  -e MCGRAVITY_SERVERS="http://mcp1:3001,http://mcp2:3001" \
  tigranbs/mcgravity

Production-Ready Features

• Health Checks: The /health endpoint returns 200 when at least one upstream server is healthy
• Automatic Retries: Configurable retry logic for failed requests
• Weighted Load Balancing: Distribute load based on server capacity
• Request Timeouts: Prevent hanging connections from degrading performance

McGravity fills the infrastructure gap that every serious MCP deployment eventually needs. Instead of building your own load balancing logic, you get a battle-tested solution that follows proven patterns from the web server world.

Ready to scale your MCP infrastructure? Check out the repository and start load-balancing your MCP servers today.