Serena

Add to your client

Copy the config for your MCP client and paste it into its config file.

{
  "mcpServers": {
    "serena": {
      "command": "uvx",
      "args": [
        "--from",
        "git+https://github.com/oraios/serena",
        "serena",
        "start-mcp-server"
      ]
    }
  }
}

Before you start

• uv (the Python package/tool manager) installed — it bootstraps and runs Serena
• Python 3.11+ (the project targets recent Python; 3.13 recommended)
• Language servers for the languages you use are auto-downloaded on first use; some ecosystems (e.g. Java, C#) may need their toolchain installed
• No API key or account required — Serena runs locally against your repo

About Serena

Tools & capabilities (11)

When to use it

• Use it when an agent needs to refactor or rename a symbol safely across a large codebase without re-reading every file
• Use it when you want precise, structural edits (replace a function body, add a method) instead of fragile whole-file rewrites
• Use it when token budget matters — retrieve only relevant symbols rather than dumping files into context
• Use it when you want to add IDE-like 'find references' / 'go to definition' powers to Claude Code, Cursor, or VS Code
• Use it when working in a polyglot repo (40+ languages via LSP) and need consistent semantic navigation
• Use it when an agent should remember facts about a project across sessions via persistent memories

Quick setup

1. 1Install uv (e.g. via the official installer or your package manager)
2. 2Register Serena with your MCP client, typically by running it via uvx/uv tool from the oraios/serena repo over stdio
3. 3Point it at your project (run `serena` in the repo or pass the project path) so it can index and start the right language server
4. 4Restart your MCP client (Claude Code/Desktop, Cursor, VS Code) so it picks up the new server
5. 5Verify by asking the agent to outline a file or find references to a symbol; the language server downloads on first use

Serena FAQ