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Evidence for your next connection.

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

Read-only probes

MCP server · Communication & messaging

Couryo free email tools

Free, no login: verify an email address, check SPF/DKIM/DMARC, explain SMTP errors, build SPF/DMARC.

Checks passed
12 / 22

2 failed · 8 not measured

Median response
365 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

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

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?
312

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 365 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name couryo-free-tools.

  • 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 365 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 365 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

    10 of 16 parameters have a description (63%). 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.

  • Fail
    Source repo linked

    No 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 2026-10-24T00:00:38.494998Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Couryo free email tools

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 couryo-free-email-tools https://mcp.couryo.com/tools

Capabilities

Tools 6

check_domain_dns

Checks the email setup of any domain: SPF (one record, ending, the 10 DNS lookup limit), DKIM on the common selectors (or dkim_selector), DMARC policy and reports, MX and mailbox provider, MTA-STS, TLS-RPT and BIMI. Answers a 0 to 100 score, a grade, the fix for each problem in plain words and records ready to copy. Free, read only. / Confere SPF, DKIM, DMARC e MX de qualquer domínio, com nota e a correção de cada problema.

Discovered
explain_smtp_error

Explains a bounce or SMTP error text ("550 5.7.515 Access denied", "452 4.2.2 mailbox full") in plain words: hard (the address does not work), soft (temporary) or policy (a provider rule, not the address), the provider and the next step. Free, read only. / Explica uma devolução ou erro SMTP em linguagem simples, com o próximo passo.

Discovered
generate_dmarc

Builds one DMARC record (TXT at _dmarc.<domain>). Start with policy none and a report address (rua), read the reports, then move to quarantine and reject once every legitimate sender passes SPF or DKIM aligned. Free, no network. / Monta o registro DMARC; comece com p=none e suba para quarantine e reject.

Discovered
generate_spf

Builds one SPF record (TXT at the domain) from the services that send for it: includes, IPv4 and IPv6, mx and a. Starts with ~all (softfail), the safe choice; use policy fail (-all) once every sender is listed. Remember the limit of 10 DNS lookups (each include costs at least one). Free, no network. / Monta o registro SPF a partir dos serviços que enviam pelo domínio.

Discovered
verify_email

Checks one email address without sending anything: format, typo in big providers ("gmail.com.br" → "gmail.com", "hotmial.com"), disposable inbox, shared mailbox (contato@, sales@) and whether the domain receives email (MX). Verdict valid, risky or invalid, with did_you_mean. The mailbox itself is never probed. Free, read only. / Confere um endereço sem enviar nada: formato, erro de digitação, e-mail temporário, caixa compartilhada e se o domínio recebe e-mail.

Discovered
verify_emails

Batch of verify_email: the same checks for up to 100 addresses at once, one verdict each (valid, risky, invalid) plus the totals. Run it before a send and drop invalid and disposable addresses. Each address counts in the daily limit. Free, read only. / Confere até 100 endereços de uma vez antes de um envio.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected365 ms6