Neovim MCP Server

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A Model Context Protocol (MCP) server that provides seamless integration with Neovim instances, enabling AI assistants to interact with your editor through connections and access diagnostic information via structured resources. Supports both stdio and HTTP server transport modes for different integration scenarios.

Features

  • Multi-Connection Support: Manage multiple concurrent Neovim instances
  • LSP Integration: Complete LSP workflow with code actions, hover, and diagnostics
  • Universal Document Identifier: Work with files by buffer ID, relative path, or absolute path
  • MCP Resources: Structured diagnostic data via connection-aware URI schemes
  • Multi-Transport Support: Both stdio and HTTP server transport modes
  • Dynamic Tool System ⚠️ (Experimental): User-extensible custom tools
  • Plugin Integration: Automatic setup through Neovim plugin

Installation

Use Cargo install from crates.io

cargo install nvim-mcp

Using Nix

This repository is a flake that exposes the server as its default package and app.

Run it directly, without installing anything:

nix run github:linw1995/nvim-mcp -- --version

Or install it imperatively into your profile:

nix profile install github:linw1995/nvim-mcp

Declarative setup with home-manager

The snippet below installs the Neovim plugin and the server binary, then registers it with Claude Code declaratively. No cargo install build step and no manual claude mcp add:

# flake.nix
inputs.nvim-mcp.url = "github:linw1995/nvim-mcp";

# home-manager module (inputs must be in scope)
{ pkgs, lib, inputs, ... }:
let
  nvim-mcp = inputs.nvim-mcp.packages.${pkgs.system}.default;
in
{
  programs.neovim = {
    enable = true;
    plugins = [
      (pkgs.vimUtils.buildVimPlugin {
        pname = "nvim-mcp";
        version = inputs.nvim-mcp.shortRev or "unstable";
        src = inputs.nvim-mcp;
      })
    ];
    extraLuaConfig = ''require("nvim-mcp").setup({})'';
  };

  # Requires home-manager's programs.claude-code module.
  programs.claude-code = {
    enable = true;
    mcpServers.nvim = {
      type = "stdio";
      command = lib.getExe nvim-mcp;
      args = [ "--connect" "auto" ];
    };
  };
}

This registers the nvim MCP server for every project, so you can skip the manual claude mcp add step below.

Tip: git spawns throwaway Neovim instances to edit commit, merge and rebase messages. If those load your full config they each call setup() and register an extra socket in the same git root. Guard the call so exactly one socket exists per repository:

local transient = false
for _, arg in ipairs(vim.fn.argv()) do
  if arg:match("COMMIT_EDITMSG$") or arg:match("MERGE_MSG$")
    or arg:match("git%-rebase%-todo$") or arg:match("TAG_EDITMSG$") then
    transient = true
  end
end
if not transient then
  require("nvim-mcp").setup({})
end

From Source

git clone https://github.com/linw1995/nvim-mcp.git && cd nvim-mcp
cargo install --path .

Usage Cases Collection

  • LSP Hover Translation (From #85)
  • Diagnostic Analysis and Code Fixes (From #10)
  • Smart Context Retrieval (From #86)
  • And more in Discussions

Quick Start

1. Setup Neovim Integration

With a plugin manager like lazy.nvim:

return {
    "linw1995/nvim-mcp",
    build = "cargo install --path .",
    opts = {},
}

2. Configure claude or other MCP clients

# Auto-connect to current project Neovim instances (recommended)
claude mcp add -s local nvim -- nvim-mcp --log-file . \
  --log-level debug --connect auto

# Analyze diagnostics in current Neovim instance
claude "analyze @nvim:nvim-diagnostics://"

Documentation

For detailed information, see:

Development

Basic development setup:

# Enter development shell
nix develop .

# Run tests
cargo test -- --show-output

# Build and run
cargo run -- --connect auto

See Development Guide for complete setup instructions, testing procedures, and contribution guidelines.