Where does the config file go?

Each app keeps it in its own place. Claude Desktop uses claude_desktop_config.json in its settings folder, Cursor uses .cursor/mcp.json and VS Code uses .vscode/mcp.json in your project. Windsurf, Claude Code and Gemini CLI use their own settings files.

Is it safe to put API keys in the config?

The file is plain text on your disk, so anyone with access to it can read the key. Use environment variables or, in VS Code, inputs that the editor asks for and stores safely. The tool warns when it sees a secret in plain text.

Are my files uploaded?

No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.

Is it free? Are there limits or watermarks?

Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.

Does it work offline?

Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.

Home / AI Builder / MCP Config Builder

MCP Config Builder

Build Model Context Protocol server configs for Claude Desktop, Cursor, VS Code, Windsurf, Claude Code and Gemini CLI, or convert one app's config to another.

Free, no uploads, no sign-up. Runs 100% in your browser.

How MCP Config Builder works

Everything runs in your browser. Prompts, datasets and model files are never uploaded. Servers are kept in one neutral list (a command with arguments and environment, or a remote URL with headers) and written in each app's own shape: mcpServers, servers with types, serverUrl or httpUrl, or claude mcp add commands. Checks warn about secrets in plain text, npx without -y, relative paths and plain http URLs.

Input: JSON. Output: JSON, Text.

How to use MCP Config Builder

Add servers from the presets or type your own command or URL.
Pick the app you use.
Read the warnings and copy or download the config.
Paste an existing config into Import to move it to another app.

Tips

In VS Code, secrets can become inputs that the editor asks for once and stores safely.
Use full paths in arguments, because apps start servers from their own folder.

MCP Config Builder FAQ

Where does the config file go?: Each app keeps it in its own place. Claude Desktop uses claude_desktop_config.json in its settings folder, Cursor uses .cursor/mcp.json and VS Code uses .vscode/mcp.json in your project. Windsurf, Claude Code and Gemini CLI use their own settings files.
Is it safe to put API keys in the config?: The file is plain text on your disk, so anyone with access to it can read the key. Use environment variables or, in VS Code, inputs that the editor asks for and stores safely. The tool warns when it sees a secret in plain text.
Are my files uploaded?: No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
Is it free? Are there limits or watermarks?: Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
Does it work offline?: Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.

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