About MCPShim

Turn any MCP server into a standard CLI command your agent can call directly.

The story

MCP servers are powerful, but using them is harder than it should be. Every MCP server has its own transport, its own auth flow, and its own way of exposing tools. An agent that wants to use tools from three different MCP servers has to manage three connections, three authentication schemes, and three different lifecycles.

Most AI agents already know how to run shell commands. They can call grep, curl, or git without thinking twice. So the question became: what if every MCP tool worked the same way - as a plain CLI command?

That's what MCPShim does. It connects to remote MCP servers, handles all the authentication, and exposes each tool as a simple command-line program. Your agent just runs a command and gets the result. No SDK, no protocol knowledge, no connection management.

“One daemon. Every MCP server. Standard CLI commands.”

The agent doesn't need to know it's talking to an MCP server at all. It runs a command, passes arguments, and reads the output. That's it.

How it's designed

CLI-first, always

Every MCP tool becomes a regular CLI command. Your agent calls it the same way it calls any other program on the system. Arguments go in, results come out. No special protocol, no client library required.

Auth is handled for you

OAuth flows, API keys, token refreshes - MCPShim manages all of it. You authenticate once during setup, and the daemon keeps credentials fresh in the background. Your agent never sees a login screen.

Composable by nature

Because everything is a CLI command, you can pipe output through jq, chain tools together in a shell script, or let your agent mix MCP tools with any other command-line program. Standard Unix patterns just work.

All servers, one interface

Add as many MCP servers as you need. Each one gets its own set of CLI commands, all sharing the same calling convention. One daemon handles every connection, every protocol detail, and every reconnection.

What it's built with

MCPShim is written in Go and ships as a single binary. No runtime dependencies, no containers required. Install it and it just works.

Language

Go

Protocol

Unix socket + JSON

Storage

SQLite

License

Open source

Under the hood, a single daemon process (mcpshimd) maintains connections to every configured MCP server. Lightweight CLI wrappers talk to the daemon over a Unix socket. Everything stays local, fast, and private.

Who it's for

MCPShim is built for AI agents and the developers who build them. If your agent needs to:

  • Use tools from remote MCP servers without managing connections
  • Call MCP tools the same way it calls grep, curl, or any shell command
  • Authenticate to multiple services once and never think about it again
  • Combine MCP tools with local commands in shell scripts and pipelines
  • Run headless on a server with no browser or UI required

…then MCPShim is the missing piece. Your agent focuses on reasoning. MCPShim gives it the tools.

Built with care

MCPShim is an open source project by CBK AI. You can explore the code, report issues, or contribute on GitHub.

Also check out Pantalk — a sibling project that gives AI agents a unified interface to chat platforms like Slack, Discord, and Telegram.