[!노트]

금속 v1.6.6 (Osmium), 금속은 이제 Coursier (cs install metals-mcp])를 통해 설치할 수있는 내장 독립 MCP 서버 (metals-mcp)를 포함합니다. 이것은 금속 내전 클라이언트 프로젝트를 불필요하게 만듭니다. 대신 공식 metals-mcp 명령을 사용하십시오.

금속 독립 MCP 클라이언트

MCP (Model Context Protocol) 지원으로 금속 언어 서버를 출시하는 독립 클라이언트는 Scala 프로젝트와 상호 작용하는 AI 조수를 가능하게합니다. 빠른 편집 및 쉬운 배포를위한 scala-cli로 내장.

목적

이 도구는 MCP 기능을 사용하여 금속 언어 서버를 실행하는 헤드리스 방법을 제공합니다. Claude와 같은 AI 코드 조수를 사용하여 Scala codebase를 이해하고 작업할 수 있습니다. 자동으로 금속 설치를 발견하고 언어 서버를 구성하고 MCP 서버의 건강을 모니터링합니다.

왜이 필요하고 어떻게 작동합니까?

금속은 일반적으로 편집기 (VS Code, Neovim 등) 내에서 실행되는 Scala 언어 서버입니다. 편집기는 LSP 클라이언트로 작용합니다: 그것은 금속을 발사하고, 초기화 Handhake를 실행하고, 윤곽을 보냅니다. 이 작업을 수행하는 편집기없이, 금속은 시작되지 않습니다.

[!NOTE]

As of Metals v1.6.6 (Osmium), Metals now includes a built-in standalone MCP server (metals-mcp) that can be installed via Coursier (cs install metals-mcp). This makes the metals-standalone-client project unnecessary. Please use the official metals-mcp command instead.

Metals Standalone MCP Client

A standalone client that launches the Metals language server with MCP (Model Context Protocol) support, enabling AI assistants to interact with Scala projects. Built with scala-cli for fast compilation and easy distribution.

Purpose

This tool provides a headless way to run Metals language server with MCP capabilities, allowing AI code assistants like Claude to understand and work with your Scala codebase. It automatically discovers Metals installations, configures the language server, and monitors MCP server health.

Why is this needed and how does it work?

Metals is a Scala language server that normally runs inside an editor (VS Code, Neovim, etc.). The editor acts as an LSP client: it launches Metals, performs the initialization handshake, and sends configuration. Without an editor doing this work, Metals doesn’t start.

This standalone client replaces the editor. It acts as a headless LSP client so that Metals can run without any editor open. Here’s what happens when you run it:

1. The standalone client discovers and launches Metals as a subprocess (via Coursier).
2. It performs the LSP handshake over stdin/stdout (initialize, initialized) using JSON-RPC 2.0.
3. It configures Metals to enable its built-in MCP server by sending startMcpServer: true.
4. Metals starts the MCP server and writes a .mcp.json file at your project root with the connection URL:

   {
     "mcpServers": {
       "metals": {
         "url": "http://localhost:/mcp",
         "type": "http"
       }
     }
   }
   

5. The standalone client monitors the MCP server health via HTTP polling to make sure it stays up.

Once this is running, you can open Claude Code (or another MCP-aware AI assistant) in your Scala project directory.

This gives AI assistants access to Scala language intelligence (go-to-definition, find-references, completions, diagnostics, etc.) without requiring an IDE.

For a detailed diagram and component breakdown, see ARCHITECTURE.md.

Quick Start

Download Pre-built Executables

Linux:

wget https://github.com/jpablo/metals-standalone-client/releases/latest/download/metals-standalone-client-linux-executable
chmod +x metals-standalone-client-linux-executable
./metals-standalone-client-linux-executable --help

macOS:

wget https://github.com/jpablo/metals-standalone-client/releases/latest/download/metals-standalone-client-macos-executable
chmod +x metals-standalone-client-macos-executable
./metals-standalone-client-macos-executable --help