Couryo free email tools

com.couryo/toolscouryo.comstreamable-httpv1.0.0Scanned 54 minutes ago

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

5 tools: 4 change things and 1 only read.

Reads private data · 0
Reads text others write · 2
Can send data out · 0
2 findings

Anlyon alternative

4 of these tools change something. Run those as governed actions.

Declare what an action changes, and Anlyon puts it under a shared limit, binds every approval to the exact request, and grades the outcome. It works on any HTTPS API you can describe as an action.

Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.

Import an OpenAPI spec →

Tools

Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.

5 tools

Changes things 4Creates or changes something that can be changed back.Claude Code: ask

check_domain_dnsChecks 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 p…Reads text others writeNo findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
Description, as the server wrote it
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.
Annotations the server declares
- readOnlyHint: true
- openWorldHint: true
generate_dmarcBuilds one DMARC record (TXT at _dmarc.<domain>).1 finding
Why it is in this group
- The name "generate_dmarc" says "generate": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
  The server marks "generate_dmarc" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"openWorldHint":false}; The name "generate_dmarc" says "generate": a word for a change.
  What this check looks for
Description, as the server wrote it
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.
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
generate_spfBuilds one SPF record (TXT at the domain) from the services that send for it: includes, IPv4 and IPv6, mx and a.1 finding
Why it is in this group
- The name "generate_spf" says "generate": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
  The server marks "generate_spf" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"openWorldHint":false}; The name "generate_spf" says "generate": a word for a change.
  What this check looks for
Description, as the server wrote it
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.
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false
verify_emailChecks one email address without sending anything: format, typo in big providers ("gmail.com.br" → "gmail.com", "hotmial.com"), disposable inbox, shared mailbox (contato@, sales@) …Reads text others writeNo findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
Description, as the server wrote it
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.
Annotations the server declares
- readOnlyHint: true
- openWorldHint: true

Only reads 1Looks things up and changes nothing.Show 1 read-only tool

explain_smtp_errorExplains 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 provide…No findings
Why it is in this group
- The name "explain_smtp_error" says "explain": a word for reading.
Description, as the server wrote it
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.
Annotations the server declares
- readOnlyHint: true
- openWorldHint: false

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Exfil surface

Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.

No private-data, untrusted-input, outbound path in this server alone: no tool is tagged private-data or outbound.

Reads private data0: Reads files, mail, messages, databases, secrets, calendars or repositories.
Reads text others write2: Brings in text someone else can write: web pages, inbound email, messages, issues and comments.; check_domain_dns
verify_email
Can send data out0: Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.

Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.

Findings

Matches of fixed checks, with the text they matched.

2 warn

Warngenerate_spf
The server marks "generate_spf" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"openWorldHint":false}; The name "generate_spf" says "generate": a word for a change.
What this check looks for
Warngenerate_dmarc
The server marks "generate_dmarc" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"openWorldHint":false}; The name "generate_dmarc" says "generate": a word for a change.
What this check looks for

History

Changes to its tool definitions and to its remote endpoint, newest first.

No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.

All changes to this server

Install

Pinned to version 1.0.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http tools https://mcp.couryo.com/tools

claude mcp add --transport http tools https://mcp.couryo.com/tools

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json

{
  "permissions": {
    "allow": [
      "mcp__tools__explain_smtp_error"
    ],
    "ask": [
      "mcp__tools__verify_email",
      "mcp__tools__check_domain_dns",
      "mcp__tools__generate_spf",
      "mcp__tools__generate_dmarc"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as tools. Review it before you use it.

Capability tags behind 2 rules

mcp__tools__verify_email untrusted-input
mcp__tools__check_domain_dns untrusted-input

Keep the decision: fail CI when the tools change, follow every change, or show a badge.

Pin in CI

Fail a build when the tools you reviewed are not the tools the server serves today.

curl -s "https://anlyon.dev/api/v1/servers/com.couryo/tools/verify?hash=494ad77408c55f0221b3a8319d686db8f9d314e2f6d5f89eaf4e4b65a458ba57" | jq -e '.changed == false'

Pinned hash 494ad77408c5, from Oct 24, 2026, 00:17 UTC.

Watch

Get told when its tools change: a new tool, a new description, a new class.

https://anlyon.dev/servers/com.couryo/tools/changes.xml

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Badge

[![anlyon.dev](https://anlyon.dev/badge/com.couryo/tools.svg)](https://anlyon.dev/servers/com.couryo/tools)

Source: MCP Registry. Synced Oct 24, 2026, 00:17 UTC.