MCP Backpressure MCP Server

Backpressure and concurrency control middleware for [FastMCP](https://github.com/jlowin/fastmcp) MCP servers.

Local serverstdioPython

What is the MCP Backpressure MCP Server?

Backpressure and concurrency control middleware for FastMCP MCP servers.

The short version

  • Concurrency limiting — Semaphore-based control of parallel executions
  • Bounded queue — Optional FIFO queue with configurable size
  • Queue timeout — Automatic timeout for queued requests with cleanup
  • Structured errors — JSON-RPC compliant overload errors with detailed metrics
  • Metrics — Real-time counters for active, queued, and rejected requests
  • Callback hook — Optional notification on each overload event

The tools it exposes

The server publishes 3 tools. What each one is for:

  • Parameters — The Parameters tool exposed by this server
  • Metrics — print(f"Active: {metrics.active}") print(f"Queued: {metrics.queued}") print(f"Total rejected: {metrics.total_rejected}") print(f"Rejected
  • Linting — The Linting tool exposed by this server

More MCP options

Compare MCP servers by category, or browse hosted MCP servers if you prefer an endpoint over a local process.

Maintainer setup documentation.

How to install the MCP Backpressure MCP Server

{
  "mcpServers": {
    "backpressure": {
      "command": "uvx",
      "args": ["mcp-backpressure"]
    }
  }
}

Add to claude_desktop_config.json, then restart Claude Desktop.

Example prompts to try

  • “Use MCP Backpressure to Parameters.”
  • “Use MCP Backpressure to Metrics.”
  • “Use MCP Backpressure to Linting.”

Frequently asked questions

Backpressure and concurrency control middleware for [FastMCP](https://github.com/jlowin/fastmcp) MCP servers. Confirm the tools offered by your installed version in the connected client. Tool availability and permissions depend on the server and account configuration.