How to Install MCP in Claude Code

Full claude mcp command reference

Everything goes through the claude mcp family. The pattern for local servers: name first, then -- separates Claude flags from the server command. Environment variables go in with -e before the --. Remote servers skip the local process entirely — just a transport and a URL.

# local stdio server (npx package)
claude mcp add github -- npx -y @modelcontextprotocol/server-github

# with environment variables
claude mcp add github -e GITHUB_PERSONAL_ACCESS_TOKEN=ghp_... -- npx -y @modelcontextprotocol/server-github

# remote server over HTTP
claude mcp add --transport http unyly-gateway https://gateway.unyly.org/mcp

# manage
claude mcp list
claude mcp get github
claude mcp remove github

Scopes: local, project, user

By default the server registers for you in the current project only (local scope). Add -s user to make it available in every project on the machine. Add -s project to write it into a .mcp.json file at the repo root — commit that file and every teammate gets the server automatically. Inside a session, type /mcp to see the status of every connected server.

Troubleshooting

If a freshly added server does not answer, restart the Claude Code session first — servers connect at session start. claude mcp list shows a health indicator per server; a failing stdio server usually means Node.js is missing from PATH (check with which node / where node) or the package name is wrong. For remote servers behind OAuth, /mcp in the session walks you through authentication.