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

Read-only probes

MCP server · Data access / search

Enginemailer MCP by usefulapi

Read Enginemailer subscribers, lists and campaigns; add subscribers, create and send campaigns.

Checks passed
13 / 22

1 failed · 8 not measured

Median response
134 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
17

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Outdated check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?
310
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 134 ms.

  • Pass
    Valid handshake

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

  • Pass
    Lists tools

    tools/list returned 17 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 134 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 134 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.

  • Fail
    Parameters documented

    36 of 46 parameters have a description (78%). 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 2026-11-10T23:34:13.180413Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using Enginemailer 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 enginemailer-mcp-by-usefulapi https://enginemailer.usefulapi.io/mcp

Capabilities

Tools 17

enginemailer_add_subscriber

WRITE: add a subscriber to the account (optionally into subcategories, with custom field values). Only add people who consented to marketing email. Free accounts may insert 50 subscribers a day, paid accounts 10,000. POST /restapi/subscriber/emsubscriber/insertSubscriber.

Discovered
enginemailer_assign_campaign_recipients

WRITE: set who a campaign will go to: all subscribers, or the subscribers in the given subcategory ids (match_type any = OR, all = AND). Does not send anything. Needs a paid account. POST /restapi/campaign/emcampaign/AssignRecipientList.

Discovered
enginemailer_check_transactional_report_export

Status of a report export (Processing or Complete); when complete it includes the CSV download URL. POST /RESTAPI/V2/Submission/Report/CheckExport (read-only).

Discovered
enginemailer_create_campaign

WRITE: create a campaign DRAFT. Nothing is sent: assign recipients with enginemailer_assign_campaign_recipients, then send with enginemailer_send_campaign. The sender domain must be verified in Enginemailer; max 200 campaigns per account. Needs a paid account. POST /restapi/Campaign/EMCampaign/CreateCampaign.

Discovered
enginemailer_get_campaign_stats

Delivery results of a DELIVERED campaign: emails sent, delivered, bounces, opens, unique opens, clicks, unique clicks, unsubscribes, spam complaints. Needs a paid account. GET /restapi/campaign/emcampaign/getcampaigndeliverystatus.

Discovered
enginemailer_get_subscriber

One subscriber by email: id, status and all custom field values. GET /restapi/subscriber/emsubscriber/getSubscriber.

Discovered
enginemailer_list_campaign_categories

The categories that campaign recipients can be filtered by (id, name, description). Needs a paid account. GET /restapi/campaign/emcampaign/GetCategoryList.

Discovered
enginemailer_list_campaign_subcategories

The subcategories of one campaign category (id, name, description); use these ids in enginemailer_assign_campaign_recipients. Needs a paid account. GET /restapi/campaign/emcampaign/GetSubCategoryList.

Discovered
enginemailer_list_campaigns

List campaigns that have NOT been delivered yet (drafts and scheduled ones): id, name, subject, sender and schedule. Delivered campaigns are not listed by the API; use enginemailer_get_campaign_stats with a known id. Needs a paid account. GET /restapi/campaign/emcampaign/ListCampaign.

Discovered
enginemailer_list_custom_fields

The subscriber custom field definitions (key, name, type). Use the keys when adding or updating subscribers. GET /restapi/subscriber/emsubscriber/getCustomField.

Discovered
enginemailer_list_subscriber_categories

The subscriber category tree: each category with its subcategories (ids, names). Use the subcategory ids when adding or updating subscribers and when assigning campaign recipients. GET /restapi/subscriber/emsubscriber/getSubCategory.

Discovered
enginemailer_save_subscriber_category

WRITE: create a subscriber category (category_id 0) or update one (its id), with subcategories (subcategory_id 0 creates one). Names and descriptions max 128 characters. POST /restapi/subscriber/emsubscriber/updateCategory.

Discovered
enginemailer_send_campaign

WRITE, SENDS EMAIL TO CUSTOMERS NOW and cannot be undone: delivers the campaign to its assigned recipients immediately. The campaign needs at least one recipient and must not be scheduled or already delivered. Show the user the campaign and its audience and get their go-ahead first; set confirm to true only then. Needs a paid account. GET /restapi/campaign/emcampaign/SendCampaign.

Discovered
enginemailer_send_transactional_email

WRITE, SENDS ONE EMAIL NOW and cannot be undone: submits a transactional email to one recipient (plus optional CC/BCC). Needs a sender address on a verified domain; give either subject + content_html, or a template_id from the Enginemailer portal (the template supplies subject and sender name). Total message incl. attachments max 5 MB. Confirm the recipient and text with the user first; set confirm to true only then. POST /RESTAPI/V2/Submission/SendEmail.

Discovered
enginemailer_start_transactional_report_export

Start a CSV export of the transactional email delivery report for a period (start date at most 60 days back). Returns an export id; poll it with enginemailer_check_transactional_report_export. Creates a report file only; nothing is sent. POST /RESTAPI/V2/Submission/Report/Export.

Discovered
enginemailer_unsubscribe_subscriber

WRITE: unsubscribe a subscriber so they no longer receive campaigns. Reversing it needs the subscriber to opt in again in Enginemailer. GET /restapi/subscriber/emsubscriber/unSubSubscriber.

Discovered
enginemailer_update_subscriber

WRITE: change an existing subscriber's subcategories and/or custom fields. subcategories_mode: append (default), remove (drop the given subcategories) or replace (the given list becomes the full list). custom_fields_mode: update_given (change only the given fields) or replace_all (default; fields not given are cleared). POST /restapi/subscriber/emsubscriber/updateSubscriber.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected134 ms17