DEV Community

Chirag Kumar
Chirag Kumar

Posted on

Stop Hand-Editing MCP Configs: A Zero-Dependency Go CLI

#go #cli #opensource #mcp

If you are experimenting with Model Context Protocol (MCP) servers using AI clients like Claude Desktop, Cursor, or terminal agents, you've probably hit this friction point: managing the configuration file.

Adding a new local or remote server usually means:

  1. Hunting down the hidden mcp_config.json file (which lives in entirely different directories depending on your OS and the client you use).
  2. Manually editing a deeply nested JSON structure.

It sounds simple until you miss a comma, leave a trailing comma, or break a bracket, and suddenly your AI client crashes or fails to boot.

I got tired of breaking my configs, so I built a tiny utility to handle it straight from the terminal.

Enter agmcp

agmcp is a CLI manager written in pure Go that safely reads, patches, and writes deeply nested JSON configurations without destroying existing keys or breaking your client apps with syntax errors.

Here is a demo of how agmcp works:
agmcp Demo

Why build this?

There are package managers for everything, but MCP configs are uniquely annoying because they are just raw JSON files sitting in arbitrary system paths. I wanted a tool that was:

  • Blazing Fast & Lightweight: Written in Go using strictly the standard library (encoding/json, os, path/filepath). Absolutely no CGO.
  • Safe: It performs safe JSON patching. It won't overwrite or format over other custom settings your client might have saved in the file.
  • Frictionless: It cross-compiles for Linux and Windows, with native install scripts that handle OS-level PATH injection automatically.

Usage

Once installed, you don't even need to know where the config file is. You just run:

# Add a GitHub MCP server
agmcp add github npx -y @modelcontextprotocol/server-github

# Remove a server
agmcp remove github

# List active servers
agmcp list
Enter fullscreen mode Exit fullscreen mode

Try it out

If you are testing a lot of servers locally, give it a try. It is entirely open-source, and I'd love to get feedback from other developers on the Go architecture or the JSON patching approach.

GitHub Repository: https://github.com/simplychiragk/agmcp

Let me know what you think or if you run into any edge cases with specific MCP clients!

Top comments (0)