Claude Desktop

Claude Desktop reads its MCP servers from claude_desktop_config.json. stretto init --host claude-desktop prints the entry that runs your server behind stretto-proxy:

stretto init --host claude-desktop --domain notes \
  -- npx -y @modelcontextprotocol/server-filesystem /Users/me/notes

{
  "mcpServers": {
    "notes": {
      "command": "/Users/me/.cargo/bin/stretto-proxy",
      "args": ["--record", "~/.stretto/logs/notes", "--domain", "notes",
               "--", "npx", "-y", "@modelcontextprotocol/server-filesystem",
               "/Users/me/notes"]
    }
  }
}

Claude Desktop starts servers with a minimal PATH, so init writes the full path of the stretto-proxy it finds on yours. Merge the entry into claude_desktop_config.json, which Settings → Developer → Edit Config opens, or find it at:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json

Then quit Claude Desktop completely and open it again; it reads the file when it starts. After it prints the entry, init lists the next steps, from learning a flow to serving it: the quick start follows them.

The server's command

init resolves the proxy's path, not the server's. If Claude Desktop cannot find the server's own command either, such as npx, give its full path in args: which npx prints it.

Serve a flow

Once you have learned and reviewed a flow, run init again with it:

stretto init --host claude-desktop --domain notes \
  --flow ~/.stretto/notes.flow.json \
  -- npx -y @modelcontextprotocol/server-filesystem /Users/me/notes

"args": ["--record", "~/.stretto/logs/notes", "--domain", "notes",
         "--flow", "/Users/me/.stretto/notes.flow.json",
         "--flow-decider", "reach",
         "--", "npx", "-y", "@modelcontextprotocol/server-filesystem",
         "/Users/me/notes"]

Replace the server's entry with the new one, and restart Claude Desktop.

• Add --shadow to init to see what the flow would do before it acts (shadow mode).
• A flow learned with --habit-only has no arbiter, so init serves it with reach, which asks no model and needs no key (deciders).

When a server does not start

Claude Desktop keeps each server's stderr in its MCP logs: on macOS in ~/Library/Logs/Claude/, as mcp-server-notes.log for this server. The proxy's own messages there start with stretto-proxy:, and the first one says where the session log is. An exit status of 125 means the proxy itself failed, such as when the log directory cannot be created or the server's command cannot be started.

Any MCP host has what applies to every host: paths, credentials and the three stages of a deployment.