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

Read-only probes

MCP server · Communication & messaging

Mail Blaze MCP by usefulapi

Manage Mail Blaze lists, subscribers, templates, campaigns and reports; send transactional email.

Checks passed
13 / 22

1 failed · 8 not measured

Median response
59 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
26

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Outdated check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 59 ms.

  • Pass
    Valid handshake

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

  • Pass
    Lists tools

    tools/list returned 26 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 59 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 59 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

    32 of 68 parameters have a description (47%). 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 2026-11-10T23:34:16.396969Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using Mail Blaze 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 mail-blaze-mcp-by-usefulapi https://mailblaze.usefulapi.io/mcp

Capabilities

Tools 26

mailblaze_add_subscriber

WRITE, MAY SEND A CONFIRMATION EMAIL: add one subscriber to a mailing list. Depending on the list's settings Mail Blaze may send the person a confirmation (double opt-in) email. Only add people who agreed to receive your email. An email that is already on the list answers with a conflict error.

Discovered
mailblaze_add_subscribers_bulk

WRITE, MAY SEND CONFIRMATION EMAILS: add up to 100 subscribers to a mailing list in one request; an email already on the list is updated instead. Depending on the list's settings Mail Blaze may send confirmation emails. Only add people who agreed to receive your email.

Discovered
mailblaze_create_campaign

WRITE, SENDS EMAIL TO PEOPLE: create a campaign for a mailing list (or one of its segments) from an existing template and schedule it for send_at. Once it goes out it reaches every subscriber of the list or segment, may use sending credit and cannot be recalled. Confirm the list, segment, subject, template and send time with the user before calling. Needs a template uid (mailblaze_list_templates) and a list uid (mailblaze_list_lists).

Discovered
mailblaze_create_template

WRITE: create an email template from HTML (the tool base64-encodes it). Mail Blaze requires the HTML to contain an unsubscribe link. Sends nothing.

Discovered
mailblaze_find_subscriber_by_email

Look up a subscriber in one list by email address. Returns the subscriber (with its uid) or a not-found error.

Discovered
mailblaze_get_campaign

Get one campaign by uid: sender, subject, list, template, status and schedule.

Discovered
mailblaze_get_campaign_inbox_breakdown

Inbox-provider breakdown (e.g. Gmail, Outlook, Yahoo) of a campaign's delivery.

Discovered
mailblaze_get_campaign_summaries

Bulk report summary (sent, opens, clicks, bounces, unsubscribes) for up to 50 campaigns in one call. Read-only (it is a POST in the API only because of the id list).

Discovered
mailblaze_get_list

Get one mailing list by its uid: general settings, default sender, company details and counts.

Discovered
mailblaze_get_report_job

Status (and result when finished) of an asynchronous report job, as returned in a 202 reply with a job_id.

Discovered
mailblaze_get_subscriber

Get one subscriber of a list by subscriber uid (status, fields, dates).

Discovered
mailblaze_get_subscriber_activity

Email activity (sends, opens, clicks, bounces) of one subscriber by email address, optionally limited to one list. Cursor-paged.

Discovered
mailblaze_get_template

Get one email template by uid (name and content).

Discovered
mailblaze_get_transactional_email

Get one transactional email by uid: recipient, subject, status and timestamps.

Discovered
mailblaze_list_campaign_events

List the individual events of a campaign by kind: opens, clicks, bounces or unsubscribes. Cursor-paged: pass the reply's next_cursor back until it is null. For very large campaigns Mail Blaze answers 202 with a job_id; check it with mailblaze_get_report_job.

Discovered
mailblaze_list_campaigns

List the account's email campaigns (uid, name, status, dates). Use the campaign uid for details and reports.

Discovered
mailblaze_list_list_fields

List the fields of a mailing list (label, tag, type, required). The tags (EMAIL, FNAME, LNAME, custom ones) are the keys used when adding or updating subscribers.

Discovered
mailblaze_list_lists

List the account's mailing lists (name, uid, subscriber counts, defaults). Use the list uid in the other tools. Paged: page + per_page.

Discovered
mailblaze_list_segments

List the segments defined on a mailing list (uid, name). A segment uid can be used when creating a campaign.

Discovered
mailblaze_list_subscribers

List the subscribers of a mailing list (sets of 10 per page; use page to go on). Contains personal data (emails, names).

Discovered
mailblaze_list_templates

List the account's email templates (uid, name). A template uid is needed to create a campaign.

Discovered
mailblaze_list_transactional_emails

List the transactional emails sent through the account (uid, recipient, subject, status). Paged.

Discovered
mailblaze_resubscribe_subscriber

WRITE: set a previously unsubscribed subscriber back to subscribed so campaigns reach them again. Only do this when the person asked to be re-added (consent).

Discovered
mailblaze_send_transactional_email

WRITE, SENDS ONE EMAIL NOW: send a single one-to-one email to one recipient through Mail Blaze. It leaves immediately, uses sending credit and cannot be recalled. Give either html (the body) or template_id (a transactional template, with merge_tags covering every tag in it), not both. Confirm the recipient and content with the user before calling. Not for bulk or marketing mail; use a campaign for that.

Discovered
mailblaze_unsubscribe_subscriber

WRITE: set a subscriber's status to unsubscribed so they receive no more campaigns from this list. By default Mail Blaze also adds the address to the account's local blacklist. Do this only when the person asked to stop (or a data-protection request requires it). The subscriber record is kept.

Discovered
mailblaze_update_subscriber

WRITE: update a subscriber's name or custom fields. Pass the subscriber's current email (Mail Blaze requires it) plus only the values to change. Does not change subscription status.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected59 ms26