Claude Desktop (stdio)

Claude Desktop connects to Synced via the stdio transport. The MCP server runs as a local process that Claude Desktop spawns and communicates with over standard input/output.

Prerequisites

  • Claude Desktop installed on your machine
  • Node.js 18+ installed (required to run npx)
  • A Synced account with a connected calendar
  • A Synced API key (see Generate API Keys)

Step 1: Get Your API Key

  1. Log in to app.meetsynced.com
  2. Navigate to Settings → API Keys
  3. Click Generate New Key and give it a name like "Claude Desktop"
  4. Copy the key immediately — it is only shown once

Step 2: Edit the Claude Desktop Config

Open the Claude Desktop configuration file and add the Synced MCP server:

Config file location

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

Add the following to your config file. If the file already contains other MCP servers, merge the synced-calendar entry into the existing mcpServers object.

claude_desktop_config.json
{
  "mcpServers": {
    "synced-calendar": {
      "command": "npx",
      "args": ["-y", "@synced/mcp-server"],
      "env": {
        "SYNCED_API_KEY": "sk_live_your_api_key_here"
      }
    }
  }
}

Replace the placeholder

Replace sk_live_your_api_key_here with the actual API key you generated in Step 1.

Step 3: Restart Claude Desktop

Fully quit and reopen Claude Desktop for the config changes to take effect. On macOS, use Cmd + Q to ensure the app is fully closed before reopening.

Step 4: Verify the Connection

Once Claude Desktop restarts, you should see a hammer icon in the message input area indicating MCP tools are available. Try these commands to confirm everything is working:

Check your meetings

"What meetings do I have this week?"

Check availability

"Am I free tomorrow afternoon?"

Schedule a meeting

"Schedule a 30-minute call with sarah@acme.com next Tuesday at 2pm"

Find optimal times

"Find the best time for a 1-hour meeting with alex@company.com and jordan@company.com"

Claude will call the appropriate Synced MCP tool and respond with real data from your calendar.

Troubleshooting

No hammer icon / tools not appearing

  • Ensure you fully quit and reopened Claude Desktop (not just closed the window)
  • Verify the JSON syntax in your config file is valid — a missing comma or bracket will silently fail
  • Check that the config file is in the correct location for your operating system

"Could not connect to MCP server"

  • Confirm Node.js 18+ is installed by running node --version in your terminal
  • Ensure npx is available on your system PATH
  • Try running npx -y @synced/mcp-server manually in your terminal to check for errors

"Authentication failed" or "Invalid API key"

  • Double-check that your API key is correct and has not been revoked
  • Make sure you replaced the placeholder sk_live_your_api_key_here with your actual key
  • Ensure there are no extra spaces or line breaks in the key value

Tools work but return empty data

  • Verify that your Synced account has a connected calendar (Google Calendar or Microsoft Outlook)
  • Check that the calendar has events in the time range you are querying
  • Visit app.meetsynced.com to confirm your calendar sync is active

View MCP logs

Claude Desktop writes MCP server logs that can help diagnose issues. On macOS, check ~/Library/Logs/Claude/ for log files related to MCP server connections.

Next Steps