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MailX Email Deliverability

REMOTE · THEMAILX.COM · SCANNED SEP 21

Check SPF/DKIM/DMARC/BIMI, blacklists, SMTP/IMAP; DNS lookups; generate email DNS records.

Available components

0 this week 87 Trust /100
Trust breakdown (7 categories)

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →

Endpoint Security74
Transport & Reachability100
Schema Quality & AI Usability88
  • 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
  • AI-judged instruction clarity (excellent).Pass
  • Tool/resource definitions use about 1483 tokens (~82/item across 18 items; 16 tools + 2 resources), lean.Pass
  • Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
  • No destabilizing schema changes in the last 30 days.Pass
Tool Coverage100
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 100% of tool parameters carry a description.Pass
Tool Safety100
  • No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
  • We read all 16 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
  • An AI judge read all 18 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
  • Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Install

How do I install the MailX Email Deliverability MCP server?

MailX Email Deliverability is a hosted endpoint at https://themailx.com/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

remote · themailx.com

# add to Claude Code
claude mcp add --transport http com-themailx-email-deliverability 'https://themailx.com/mcp'
// .cursor/mcp.json
{
  "mcpServers": {
    "com-themailx-email-deliverability": {
      "url": "https://themailx.com/mcp"
    }
  }
}
// .vscode/mcp.json
{
  "servers": {
    "com-themailx-email-deliverability": {
      "type": "http",
      "url": "https://themailx.com/mcp"
    }
  }
}
# ~/.codex/config.toml
[mcp_servers.com-themailx-email-deliverability]
url = "https://themailx.com/mcp"
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "com-themailx-email-deliverability": {
      "type": "remote",
      "url": "https://themailx.com/mcp",
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add com-themailx-email-deliverability --url 'https://themailx.com/mcp' --transport streamable-http
# ~/.hermes/config.yaml
mcp_servers:
  com-themailx-email-deliverability:
    url: "https://themailx.com/mcp"
// ~/.netclaw/config/netclaw.json
{
  "McpServers": {
    "com-themailx-email-deliverability": {
      "Transport": "http",
      "Url": "https://themailx.com/mcp"
    }
  }
}
# add to Vellum
assistant mcp add com-themailx-email-deliverability -t streamable-http -u 'https://themailx.com/mcp'
// mcp.json
{
  "mcpServers": {
    "com-themailx-email-deliverability": {
      "type": "http",
      "url": "https://themailx.com/mcp"
    }
  }
}

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 26 Aug 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 25 Aug 26 0
    • Stability: 0.97 → pass security
  • 24 Aug 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.

  • 11 Aug 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 31 Jul 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 27 Jul 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 26 Jul 26 0

    First indexed and scored.

Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 21 Sept 2026 · Probed https://themailx.com/mcp

TLS valid

Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .

Subject Issuer Valid from Valid until Key Signature Serial
CN=themailx.com CN=Amazon RSA 2048 M04,O=Amazon,C=US 21 Aug 2026 6 Mar 2027 RSA 2048 SHA256-RSA 38d3b48b2366bd2b2d2439d1db2f0f3
SANs: themailx.com, *.themailx.com
CN=Amazon RSA 2048 M04,O=Amazon,C=US (CA) CN=Amazon Root CA 1,O=Amazon,C=US 23 Aug 2022 23 Aug 2030 RSA 2048 SHA256-RSA 773124f2a952e3ed18a58bdb85d1bc0ce5f27
CN=Amazon Root CA 1,O=Amazon,C=US (CA) CN=Starfield Services Root Certificate Authority - G2,O=Starfield Technologies\, Inc.,L=Scottsdale,ST=Arizona,C=US 25 May 2015 31 Dec 2037 RSA 2048 SHA256-RSA 67f944a2a27cdf3fac2ae2b01f908eeb9c4c6

Background: What to check on a remote MCP endpoint →

DNSSEC insecure

Validation of themailx.com. Not signed

Zone DS Keys Algorithms Outcome
. trust_anchor 20326, 38696 8, 8 Verified
com. present 19718 13 Verified
themailx.com. absent Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation
Authentication No authorisation required

The endpoint answered without asking for a token. Anyone who knows the URL can reach it.

Result No authorisation required
HTTP status 200

Background: How OAuth 2.1 works in the 2026 MCP spec →

Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://themailx.com/mcp Verified 200
http (plaintext) http://themailx.com/mcp HTTPS enforced 301 https://themailx.com/mcp
MCP tools · 16 exposed · ~1,365 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →

Tool Tokens
bimi_check ~67

Check if a domain has a valid BIMI (Brand Indicators for Message Identification) DNS record. BIMI allows brands to display their logo next to authenticated emails in supporting email clients.

NameTypeReqDescription
domain_namestringyesThe domain to check BIMI records for, e.g. example.com

No output schema declared.

No examples provided.

blacklist_check ~71

Check if a domain or IP address is listed in popular email blacklists (DNSBLs). Being blacklisted can severely impact email deliverability.

NameTypeReqDescription
domain_namestringyesThe domain name or IP address to check against blacklists, e.g. example.com or 1.2.3.4

No output schema declared.

No examples provided.

cname_lookup ~52

Look up CNAME (Canonical Name) records for a domain. Shows where a hostname aliases to.

NameTypeReqDescription
domain_namestringyesThe domain to look up CNAME records for, e.g. www.example.com

No output schema declared.

No examples provided.

dkim_check ~97

Check if a domain has a valid DKIM (DomainKeys Identified Mail) DNS record for a given selector. DKIM allows the receiver to verify that an email was sent by the domain owner.

NameTypeReqDescription
dkim_selectorstringyesThe DKIM selector to look up, e.g. google, default, selector1
domain_namestringyesThe domain to check DKIM records for, e.g. example.com

No output schema declared.

No examples provided.

dmarc_check ~73

Check if a domain has a valid DMARC (Domain-based Message Authentication, Reporting & Conformance) DNS record. DMARC tells receiving servers what to do with emails that fail SPF or DKIM checks.

NameTypeReqDescription
domain_namestringyesThe domain to check DMARC records for, e.g. example.com

No output schema declared.

No examples provided.

dmarc_generate ~115

Generate a DMARC DNS record for a domain. Returns the record name, value, and type ready to be added to DNS.

NameTypeReqDescription
dmarc_policystringyesThe DMARC policy: none (monitor only), quarantine (mark as spam), or reject (block entirely)
domain_namestringyesThe domain to generate a DMARC record for, e.g. example.com
emailstringyesThe email address to receive DMARC aggregate reports, e.g. dmarc@example.com

No output schema declared.

No examples provided.

dns_lookup ~63

Look up all DNS records for a domain in one query. Returns A, AAAA, CNAME, MX, NS, TXT, and SOA records.

NameTypeReqDescription
domain_namestringyesThe domain to look up all DNS records for, e.g. example.com

No output schema declared.

No examples provided.

imap_check ~128

Test an IMAP server connection by attempting to connect and authenticate. Use this to verify email receiving configuration.

NameTypeReqDescription
imap_encryptionstringyesThe encryption protocol: ssl, tls, or none
imap_hoststringyesThe IMAP server hostname, e.g. imap.gmail.com
imap_portintegeryesThe IMAP port number, e.g. 993 for SSL, 143 for unencrypted
passwordstringyesThe IMAP password or app-specific password
usernamestringyesThe IMAP username for authentication

No output schema declared.

No examples provided.

imap_finder ~75

Look up IMAP server settings (host, port, encryption) for a given email provider. Use this to find the correct IMAP configuration for services like Gmail, Outlook, Yahoo, etc.

NameTypeReqDescription
imap_provider_namestringyesThe email provider name to look up, e.g. gmail, outlook, yahoo

No output schema declared.

No examples provided.

mx_lookup ~51

Look up MX (Mail Exchanger) records for a domain. Returns the mail servers and their priorities.

NameTypeReqDescription
domain_namestringyesThe domain to look up MX records for, e.g. example.com

No output schema declared.

No examples provided.

ptr_lookup ~67

Reverse DNS lookup. Find the hostname associated with an IP address. A valid PTR record is important for email sending reputation.

NameTypeReqDescription
ip_addressstringyesThe IP address to look up, e.g. 8.8.8.8 or 142.250.80.46

No output schema declared.

No examples provided.

smtp_check ~186

Test an SMTP server connection by attempting to connect and authenticate. If from_email and to_email are provided, the tool may attempt to send a test email. Only provide these fields if you are authorized to send from the account and intentionally want to test full sending capability.

NameTypeReqDescription
encryptionstringyesThe encryption protocol: ssl, tls, or none
from_emailstringOptional sender email address for sending a test email
hoststringyesThe SMTP server hostname, e.g. smtp.gmail.com
passwordstringyesThe SMTP password or app-specific password
portintegeryesThe SMTP port number, e.g. 587 for TLS, 465 for SSL, 25 for unencrypted
to_emailstringOptional recipient email address for sending a test email
usernamestringyesThe SMTP username for authentication

No output schema declared.

No examples provided.

smtp_finder ~75

Look up SMTP server settings (host, port, encryption) for a given email provider. Use this to find the correct SMTP configuration for services like Gmail, Outlook, SendGrid, etc.

NameTypeReqDescription
provider_namestringyesThe email provider name to look up, e.g. gmail, sendgrid, mailgun, outlook

No output schema declared.

No examples provided.

spf_check ~62

Check if a domain has a valid SPF (Sender Policy Framework) DNS record. SPF specifies which mail servers are authorized to send email on behalf of a domain.

NameTypeReqDescription
domain_namestringyesThe domain to check SPF records for, e.g. example.com

No output schema declared.

No examples provided.

spf_generate ~126

Generate an SPF DNS record for a domain based on the email provider being used. Returns the record name, value, and type ready to be added to DNS.

NameTypeReqDescription
domain_namestringyesThe domain to generate an SPF record for, e.g. example.com
hard_fail_booleanbooleanyesIf true, uses strict -all policy (reject unauthorized senders). If false, uses soft ~all (mark but deliver).
providerstringyesThe mail provider identifier, e.g. google, mailgun, sendgrid, postmark, amazon-ses

No output schema declared.

No examples provided.

txt_lookup ~57

Look up all TXT records for a domain. TXT records contain SPF policies, domain verification tokens, DKIM keys, and other metadata.

NameTypeReqDescription
domain_namestringyesThe domain to look up TXT records for, e.g. example.com

No output schema declared.

No examples provided.

Common questions

What is the MailX Email Deliverability MCP server?

MailX Email Deliverability is an MCP server listed in the public MCP registry as com.themailx/email-deliverability. Check SPF/DKIM/DMARC/BIMI, blacklists, SMTP/IMAP; DNS lookups; generate email DNS records. This page covers its hosted endpoint (https://themailx.com/mcp).

Is the MailX Email Deliverability MCP server safe to use?

MailX Email Deliverability scores 87 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

What tools does the MailX Email Deliverability MCP server expose?

MailX Email Deliverability exposes 16 tools: spf_check, dkim_check, dmarc_check, bimi_check, dmarc_generate, and 11 more. Their descriptions and schemas cost roughly 1,365 tokens of context every time the server is loaded.

Does the MailX Email Deliverability MCP server require authentication?

No. We connected to MailX Email Deliverability without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

Is the MailX Email Deliverability MCP server still maintained?

MailX Email Deliverability is still listed as active in the MCP registry. We last reached this channel on 21 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.