Customer.io MCP server for Claude, Codex and Cursor

What your AI apps can do with Customer.io

• Review campaigns and messages
• Search people and segments

Customer.io MCP tools

8 tools, taken from the publisher's documentation on 29 October 2026. The server decides what it offers and can add or rename tools at any time; after you connect, Toolstile shows the current list.

Suggested access for each AI app

The documentation this list comes from doesn't mark Customer.io's tools as read-only or destructive. Read each tool's description and decide per app before allowing it.

Coding agent in Claude Code or Cursor. Allow the read tools so the agent can look things up without stopping, and require approval for tools that change shared data.

Chat or research app in Claude Desktop. Allow reading and searching. Allow writes only where you want the app to act for you.

Unattended agent, such as a scheduled Codex job. No one is watching the session, so keep it narrow: allow what the job needs, require approval for changes and block the rest.

Blocked tools are removed from the tool list an app sees, so it won't try them. Because rules apply per app, the same Customer.io connection can be broad in one app and read-only in another, and the credential stays in Toolstile instead of each app's config file.

How it works with Toolstile

1. Connect once. Add Customer.io to a workspace (browser sign-in). Toolstile keeps the credential, so no agent config holds it.
2. Choose access per app. Give Claude Code every Customer.io tool, give Cursor only the read tools, or keep Customer.io away from an app entirely.
3. Share approved accounts. Teammates use the connection without copying tokens, and you can remove access in one place.
4. Review activity. See which app called which tool and when, so you can tighten access with evidence.

Add the Customer.io MCP server to an AI app

Through Toolstile, every AI app uses one gateway entry, whichever servers you connect. In Claude Code:

claude mcp add --transport http toolstile 'https://toolstile.com/mcp'

Then connect Customer.io in your workspace and choose which of its tools that app may use. Client setup covers Codex, Cursor and Claude Desktop.

To connect directly instead, add the Customer.io endpoint to each app separately. In Claude Code:

claude mcp add --transport http customerio 'https://mcp.customer.io/mcp'

In Cursor's mcp.json:

{
  "mcpServers": {
    "customerio": {
      "url": "https://mcp.customer.io/mcp"
    }
  }
}

Some servers accept only clients they have approved, or need a token header. Check the Customer.io MCP documentation for what your client needs.

Before you connect

A Customer.io account. Sign-in uses your Customer.io permissions.

Server details

Customer.io MCP documentation