Customerio MCP Server

by usefulapi Your server? Claim it

answering

Customerio is answering right now. Last checked 11 min ago. It exposes 13 tools. Last commit 1 Sep 2026.

Query people, segments, campaigns, and message deliveries; send transactional email or broadcasts.

Uptime history 47 days of history · worst day 10%

47 days agonow

100.0%

Uptime 24h

91 of 91 checks

Tools

read from the server

165 ms

Response time

average over 24h

Stars

last commit 1 Sep 2026

Nothing serious here today

Today is the operative word: we check Customerio every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 11 min ago.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

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

~/Library/Application Support/Claude/claude_desktop_config.json

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

~/.codex/config.toml

[mcp_servers.customerio]
url = "https://customerio.usefulapi.io/mcp"

.cursor/mcp.json

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

.vscode/mcp.json

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

Available tools 13

Read directly from the server with tools/list, grouped by what they act on. If a tool disappears, we record the date.

customerio

customerio_get_campaign

Get a single campaign by id. App API: GET /v1/campaigns/{campaign_id}.

customerio_get_campaign_metrics

Get delivery/engagement metrics for a campaign over time. App API: GET /v1/campaigns/{campaign_id}/metrics.

customerio_get_customer_attributes

Get a single person's attributes (profile fields). App API: GET /v1/customers/{customer_id}/attributes.

customerio_get_customer_messages

List messages (deliveries) sent to a single person. App API: GET /v1/customers/{customer_id}/messages.

customerio_get_customer_segments

List the segments a single person belongs to. App API: GET /v1/customers/{customer_id}/segments.

customerio_list_campaigns

List all campaigns in the workspace. App API: GET /v1/campaigns.

customerio_list_collections

List reusable data collections in the workspace. App API: GET /v1/collections.

customerio_list_exports

List data exports in the workspace. App API: GET /v1/exports.

customerio_list_messages

List sent messages (deliveries) across the workspace, filterable by type/campaign/newsletter. App API: GET /v1/messages.

customerio_list_segments

List all segments in the workspace (id + name + type). App API: GET /v1/segments.

customerio_search_customers

Search/list people by a Customer.io filter (segment or attribute conditions). e.g. filter={"segment":{"id":7}} or {"and":[...]}. App API: POST /v1/customers.

customerio_send_transactional_email

⚠️ SENDS A REAL EMAIL. Send a transactional email using a transactional message template. Delivers immediately to the `to` recipient. App API: POST /v1/send/email.

customerio_trigger_broadcast

⚠️ SENDS TO REAL RECIPIENTS. Trigger an API-triggered broadcast, delivering to the resolved recipient set. App API: POST /v1/send/broadcast (posts to /v1/campaigns/{broadcast_id}/triggers).

Endpoints

URL	Transport	State	Latency	Checked
https://customerio.usefulapi.io/mcp	streamable-http	answering	206 ms	11 min ago

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Customerio — questions

Answers built from our own checks of this server.

What can Customerio do?

It exposes 13 tools, read directly from the server on our last check. Among them: customerio_get_campaign, customerio_get_campaign_metrics, customerio_get_customer_attributes, customerio_get_customer_messages, customerio_get_customer_segments, customerio_list_campaigns and 7 more. The full list with descriptions is on this page — we take it from the server itself via tools/list, not from a README. How MCP servers expose tools in the first place →

Is Customerio working right now?

We send a real MCP handshake every 15 minutes. Over the last 24 hours 91 of 91 checks got a reply (100.0%), average response time 165 ms. The bar chart above shows every period we have measured.

How do I connect Customerio?

Copy the ready config from this page — we generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each with the file path that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address.

Does Customerio need an API key?

No. Customerio completed a full MCP handshake with us as an anonymous client and listed its tools without asking for anything. All 13 of them are readable on this page. This is what we observed, not what the docs claim.

How fast is Customerio?

It answers our handshake in 165 ms on average, which is faster than 73% of all working MCP servers we measure. The comparison comes from our own checks across the whole registry, every 15 minutes.

Is Customerio open source?

Yes — it is published under the MIT licence, written in JavaScript and 0 stars on GitHub. The source link is on this page, so you can read exactly what it does with your data before you connect it.