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

Read-only probes

MCP server · Communication & messaging

MailerCheck MCP by usefulapi

By usefulapi.io Verified namespace

Check MailerCheck credits and lists, and run confirmed asynchronous email verification.

WebsiteSource codeProductivity & docs
Connect to MailerCheck MCP by usefulapi
Checks passed
13 / 22

1 failed · 8 not measured

Median response
65 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
6

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Outdated check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 65 ms.

  • Pass
    Valid handshake

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

  • Pass
    Lists tools

    tools/list returned 6 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 65 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 65 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

    0 of 6 parameters have a description (0%). 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 2026-11-10T23:34:25.900263Z, within 180 days.

  • Not measured
    Open-source licence

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

Start using MailerCheck 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 mailercheck-mcp-by-usefulapi https://mailercheck.usefulapi.io/mcp

Capabilities

Tools 6

mailercheck_account

Read the connected MailerCheck account name, ID and credit balance. Does not verify emails or spend verification credits.

Discovered
mailercheck_credits

Read the available MailerCheck verification credit balance without starting verification.

Discovered
mailercheck_get_list

Read one existing list's verification status and aggregate result counts. Does not start or restart verification.

Discovered
mailercheck_lists

Read one bounded page of list summaries, processing status and statistics. Does not create, verify or delete lists. Pagination stays on the MailerCheck API; no response links are followed.

Discovered
mailercheck_verification_result

Read the status and result of a previously submitted asynchronous email check. Does not start new verification. Call once and wait before polling again; no automatic polling is performed.

Discovered
mailercheck_verify_email

Submit one email for asynchronous verification. Spends MailerCheck credits and requires confirm:true. This call is never retried. Read the returned verification ID with mailercheck_verification_result; wait between polls. If the response is lost, check MailerCheck before submitting again.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected65 ms6

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