Install Klaviyo MCP in Claude Code

What you need first

• Claude Code, installed.
• Node.js, which gives the npx command the server starts with.
• Your own value for YOUR_KLAVIYO_KEY_MAIN.

Steps

1. Run this in a terminal, in the project folder. It adds the server for you in that project; put --scope user after claude mcp add to have it in every project.

claude mcp add --env KLAVIYO_KEY_MAIN=YOUR_KLAVIYO_KEY_MAIN --transport stdio klaviyo-mcp -- npx -y @scalably-io/[email protected]

2. Replace YOUR_KLAVIYO_KEY_MAIN with your own value.
3. Start Claude Code and type /mcp: the server is listed with its state.

Check it worked

Ask Claude Code: List the tools of klaviyo-mcp.

If it does not start

spawn npx ENOENT

Node.js is not on the PATH that Claude Code sees. Install it, or write the full path of npx in the config.

The server starts, but its tools fail

A YOUR_… placeholder is still in the config, or its value is wrong.