How to add MCP servers to Claude Code

1. Find the config file

• .mcp.json (project, shared)
• ~/.claude.json (user / local scope)

Remote entries need "type": "http" (or "sse"); an entry with a url but no type is read as stdio and skipped.

2. Add a local (stdio) server

Example: Context7, which runs locally with npx.

claude mcp add --transport stdio context7 -- npx -y @upstash/context7-mcp

{
  "mcpServers": {
    "context7": {
      "command": "npx",
      "args": [
        "-y",
        "@upstash/context7-mcp"
      ]
    }
  }
}

3. Add a remote (HTTP) server

Example: Notion's hosted server. You sign in with OAuth the first time it connects.

claude mcp add --transport http notion https://mcp.notion.com/mcp

{
  "mcpServers": {
    "notion": {
      "type": "http",
      "url": "https://mcp.notion.com/mcp"
    }
  }
}

4. If it won't connect

• Validate the file. One trailing comma breaks the whole file.
• Check the top-level key: VS Code uses servers; Claude Code, Cursor and Antigravity use mcpServers; Codex uses TOML tables.
• If npx isn't found, the app may not see your shell's PATH (common with nvm). Use the full path to npx.
• Restart the agent or reload the window after editing.