MCP (Model Context Protocol) is not a plugin. Not a skill. Not an API. It's a protocol — an open standard that defines how an AI agent communicates with external tools. Think USB, but for connecting Claude to your services: Notion, GitHub, Sentry, databases, whatever you need.
TL;DR
claude mcp add+ URL or local command. That's all it takes to connect Claude to any service.
The key distinction: a skill is a prompt you give Claude. An API is something you consume from your code. MCP is something Claude consumes directly — it gives Claude new tools it can use without you writing any code.
Result:
> /mcp
MCP Servers:
● notion (http, connected)
● db (stdio, connected)
The two types of servers
1. Remote (HTTP) — cloud services
An HTTP server lives on the internet. Someone else maintains it, you just connect:
# Notion
claude mcp add --transport http notion https://mcp.notion.com/mcp
# GitHub
claude mcp add --transport http github https://api.githubcopilot.com/mcp/
Some require OAuth authentication. After adding, run /mcp inside Claude Code and follow the browser flow.
2. Local (stdio) — processes on your machine
A stdio server is a process running locally. Ideal for databases, system tools, or custom scripts:
# PostgreSQL
claude mcp add --transport stdio db -- npx -y @bytebase/dbhub \
--dsn "postgresql://user:pass@localhost:5432/mydb"
# Custom server
claude mcp add --transport stdio my-tool -- node ./my-mcp-server.js
Quick reference
| Command | What it does |
|---|---|
claude mcp add |
Add a server |
claude mcp list |
List configured servers |
claude mcp remove <name> |
Remove a server |
/mcp |
Status and authentication (inside Claude Code) |
| Scope | Where it's stored | Use case |
|---|---|---|
--scope local |
~/.claude.json (default) |
Just you, just this project |
--scope project |
.mcp.json at project root |
Shared with team (goes to git) |
--scope user |
~/.claude.json |
Just you, all your projects |
Official docs: Connect Claude Code to tools via MCP