Claude Code MCP Tools: Complete Setup Guide (2026)

How MCP Works in Claude Code

Claude Code supports MCP (Model Context Protocol) servers natively. When an MCP server is configured, Claude Code starts it automatically at the beginning of each session and makes its tools available to the model. You can see active MCP servers by running /mcp in a Claude Code session.

MCP tools in Claude Code work differently from built-in tools like file reading or bash execution. They run as separate processes and communicate over stdio. Claude Code manages their lifecycle — starting them when needed, passing tool calls, and receiving results.

Method 1: Using Syncore (Recommended)

Syncore is the fastest way to add MCP tools to Claude Code. It installs 50+ tools in one command and handles all configuration automatically.

Step 1: Install Syncore

curl -fsSL https://syncorelabs.ai/install.sh | sh

Step 2: Authenticate

syncore login

Step 3: Configure Claude Code

syncore setup

This writes the Syncore MCP server entry to ~/.claude/settings.json automatically. Start a new Claude Code session and run /mcp — you'll see syncore listed as an active server with all installed tools available.

Step 4: Connect your apps

Go to syncorelabs.ai/connect and connect Gmail, Slack, GitHub, Notion, or any other service. Run syncore update to sync the credentials to your machine. The tools are immediately available in your next Claude Code session.

Method 2: Manual MCP Configuration

If you prefer to configure MCP servers manually, add entries to ~/.claude/settings.json:

{
  "mcpServers": {
    "my-tool": {
      "command": "node",
      "args": ["/path/to/mcp-server/index.js"],
      "env": {
        "API_KEY": "your-key-here"
      }
    }
  }
}

Claude Code reads this file at startup and launches each configured server. The server must implement the MCP protocol over stdio.

Available Tools with Syncore

After connecting your apps, Claude Code has access to tools including:

Communication: Gmail (search, read, send, draft), Slack (send messages, read channels, search), Discord, Telegram, Microsoft Teams, Outlook

Productivity: Notion (search, read, create pages), Google Calendar (list events, create events), Linear (list issues, create issues, update status), Asana

Development: GitHub (search repos, read files, create issues, create PRs, trigger workflows), Vercel, Supabase, Figma

Research: Perplexity (web search, no API key required), Firecrawl (web scraping), SerpAPI, Tavily

Data: Google Sheets (read, write cells), Google Drive (search, upload), Airtable

Common Problems and Fixes

Problem: `/mcp` shows no servers

Claude Code didn't pick up the config. Check that ~/.claude/settings.json exists and contains the mcpServers key. If using Syncore, re-run syncore setup.

Problem: Server shows as "failed to start"

The MCP server process crashed on startup. Check the server binary path is correct and the binary is executable. For Syncore: run syncore doctor to diagnose.

Problem: Tool calls return auth errors

The OAuth token for that provider has expired. For Syncore: run syncore update to refresh credentials from the vault. If that doesn't fix it, go to syncorelabs.ai/connect and re-authorize the app.

Problem: Tools available but Claude doesn't use them

Claude needs to know the tools exist. In your prompt, explicitly mention the tool: "Use the gmail search tool to find..." — Claude will use tools more reliably when prompted to.

Problem: MCP server disconnects mid-session

Some MCP servers have idle timeouts. Claude Code will restart them automatically on the next tool call. If it's happening frequently, check for memory leaks in the server process.

Verifying Your Setup

In a Claude Code session, run:

/mcp

You'll see a list of active servers and their status. Then try a real tool call:

> "Search my Gmail for emails from GitHub in the last 7 days and list the repositories that sent notifications."

If Claude executes a tool call and returns real data, your setup is working.