Claude Desktop MCP Setup (Config File + Example)
Last updated 2026-09-14
Quick answer
Claude Desktop was the first MCP client and remains the reference implementation. Adding a server means editing one JSON file and restarting the app.
Find the config file
Claude Desktop stores MCP servers in a single JSON file. Open it from the app via Settings → Developer → Edit Config, or navigate to it directly:
- ▸macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
- ▸Windows: %APPDATA%\Claude\claude_desktop_config.json
Add a filesystem server
Paste this into the file, pointing the path at a folder you want Claude to access:
{ "mcpServers": { "filesystem": { "command": "npx", "args": ["-y", "@modelcontextprotocol/server-filesystem", "/Users/you/projects"] } } }
Restart and check
Quit Claude Desktop completely and reopen it. Click the tools icon in the composer — your server and its tools should be listed. If it is missing, open the logs via Settings → Developer and look for an error.
Passing API keys
Servers that wrap an API take keys through an env block:
{ "mcpServers": { "brave-search": { "command": "npx", "args": ["-y", "@modelcontextprotocol/server-brave-search"], "env": { "BRAVE_API_KEY": "your-key" } } } }
Frequently asked questions
Does Claude Desktop support remote MCP servers?＋
Yes. Claude supports remote servers via connectors and by referencing a url instead of a command in the config.
Why did my server not appear after restart?＋
Common causes are a JSON syntax error (trailing comma), a missing Node.js install, or an invalid API key. Check the Developer logs.
Can I run multiple MCP servers at once?＋
Yes. Add each one as a key inside the mcpServers object; Claude will load all of them.