MCP HeartbeatTHE MCP OBSERVATORY
Public workspace

Explore

Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Communication & messaging

Customer.io MCP by usefulapi

By usefulapi.io Verified namespace

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

WebsiteSource codeProductivity & docs
Connect to Customer.io MCP by usefulapi
Checks passed
14 / 22

0 failed · 8 not measured

Median response
60 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
13

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 60 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name customerio-mcp.

  • Pass
    Lists tools

    tools/list returned 13 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 60 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 60 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    34 of 34 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-11-10T23:33:22.086377Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using Customer.io MCP by usefulapi

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

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

Capabilities

Tools 13

customerio_get_campaign

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

Discovered
customerio_get_campaign_metrics

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

Discovered
customerio_get_customer_attributes

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

Discovered
customerio_get_customer_messages

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

Discovered
customerio_get_customer_segments

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

Discovered
customerio_list_campaigns

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

Discovered
customerio_list_collections

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

Discovered
customerio_list_exports

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

Discovered
customerio_list_messages

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

Discovered
customerio_list_segments

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

Discovered
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.

Discovered
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.

Discovered
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).

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected60 ms13

Related servers

All alternatives

Same function and industry, ranked by checks passed then median latency.

Explore alternatives to Customer.io MCP by usefulapi