MCP Servers

MCP stands for Model Context Protocol. It is a standard way for Claude Code to connect to real external systems — not just the files sitting in your project folder.

What Problem This Solves

By default, Claude Code only knows about your local project. If you ask it about a GitHub issue, it can only guess based on whatever title or text you typed in — it has no way to actually open GitHub and read the real issue.

An MCP server is a small connector that gives Claude Code a real, live link to an outside system. Once connected, Claude Code is no longer guessing from what you typed — it can go check the real, current data itself: a real GitHub issue, a real row in your database, a real message in a Slack channel.

Adding a Server

Here is how you connect the official GitHub MCP server:

Terminal


claude mcp add --transport http github https://api.githubcopilot.com/mcp

Once this is added, you can ask something like:


check GitHub issue #482 and summarize what the reporter is asking for

Without MCP connected, Claude Code has no way to answer this — it does not know what issue #482 even says. With the GitHub server connected, it actually opens that real issue through the connection and reads it, the same way you would if you opened the link yourself.

Popular Servers

Server	What it connects to
GitHub	Issues, pull requests, and repositories
Slack	Channels and messages
PostgreSQL	Your own database, so you can ask questions about real data
Sentry	Error reports and stack traces from production

Where the Connection Gets Saved

When you add an MCP server, the connection details are saved to a file. Which file depends on who should have access to it:

Scope	File
Just this project, just you	`.mcp.json` (local only, not shared)
This project, shared with your team	`.claude/.mcp.json`
All of your projects	`~/.claude/.mcp.json`

Only connect servers you actually trust. An MCP server can read real data, and sometimes take real actions, in whatever system it connects to — a database, a GitHub repo, a Slack workspace. Treat adding a new MCP server with the same caution you would use when installing a new software dependency.

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