gopls MCP Server

Supercharge AI's ability to understand and navigate Go code through the Model Context Protocol (MCP).

This extension automatically starts an MCP server that bridges AI assistants with Go's official language server (gopls), enabling them to analyze Go codebases with precision and context-awareness.

Why gopls-mcp?

Large language models often struggle with Go code comprehension—missing type information, unable to trace references, or hallucinating about code structure. gopls-mcp solves this by giving AI assistants the same powerful tools developers use:

🎯 Precise symbol lookup - Navigate to exact definitions, no guessing
🔍 Complete reference tracking - Find every usage of functions, types, and variables
📚 Rich type information - Access full type signatures, documentation, and interfaces
🗺️ Workspace-wide analysis - Understand relationships across your entire codebase

project repository

https://github.com/arczhi/gopls-mcp

Quick Start

1. Install Dependencies

# Install gopls (Go language server)
go install golang.org/x/tools/gopls@latest

2. Install Extension

Install this extension in VS Code. It will automatically start the MCP server on port 3000.

3. Configure Your AI Assistant

Add this to your AI assistant's MCP configuration (e.g., Claude Desktop at ~/.claude/mcp.json):

{
  "servers": {
    "gopls-mcp": {
      "url": "http://127.0.0.1:3000/sse"
    }
  }
}

That's it! The extension handles server startup automatically.

What Your AI Can Do

Once configured, AI assistants gain four powerful tools:

`go_definition`

Find where any symbol is defined—functions, types, variables, constants.

"Where is the UserRepository interface defined?"

`go_references`

Discover all locations where a symbol is used across your codebase.

"Show me everywhere the AuthenticateUser function is called"

`go_hover`

Get complete type information, function signatures, and documentation.

"What's the signature of the handler at line 45?"

`go_symbols`

List all symbols in a file or search across your entire workspace.

"List all exported functions in the api package"

Extension Settings

goplsMcp.enabled - Enable/disable the MCP server (default: true)
goplsMcp.serverPort - HTTP server port (default: 3000)
goplsMcp.workspacePath - Go workspace path (defaults to current workspace)

Commands

gopls MCP: Start Server - Manually start the server
gopls MCP: Stop Server - Stop the running server

How It Works

Extension starts main_http.py when VS Code opens
MCP server launches on http://127.0.0.1:3000
Server communicates with gopls to analyze your Go code
AI assistants connect via HTTP/SSE and invoke tools
Results return with precise, type-checked information

Troubleshooting

Server won't start?

Check Output panel (View → Output → gopls MCP Server) for errors
Verify gopls: gopls version
Verify Python deps: pip list | grep mcp

Port 3000 in use?

Change port in settings: goplsMcp.serverPort
Update AI configuration to match the new port

gopls not found?

Ensure ~/go/bin is in your PATH
Restart VS Code after installing gopls

Requirements

Go 1.18+ with gopls installed
Python 3.8+ with MCP dependencies
VS Code 1.75+

More Information

Transform how AI understands your Go code. Install gopls-mcp today.