io.github.kryptoscan由 GitHub 帳號 kryptoscan 發布v0.1.0更新於 Oct 29, 2026
Check SPF, DKIM, DMARC, blocklists, reverse DNS and email headers against Gmail/Yahoo sender rules.
唯讀的 MCP 伺服器，用來診斷郵件送達率：SPF、DKIM、DMARC、黑名單、反向 DNS 與收到的郵件標頭。
Web executable，透過 Streamable HTTP。 遠端服務在工作區中設定後即可從網頁執行環境執行。
把這段提示詞貼上到 Claude Code、Codex、Cursor 等代理程式，或 SourceWeft 對話中。代理程式會讀取該伺服器的安裝指南，先向你展示發布者、端點和登入方式，經你同意後再把它新增到你的客戶端。金鑰不會寫進任何命令。
閱讀 https://sourceweft.com/mcp/io.github.kryptoscan%2Femail-deliverability-mcp/install.md，並按其中說明把這個 MCP 伺服器接入我的客戶端。修改任何設定之前，先告訴我它的發布者、端點和登入方式，等我確認。不要把 API 金鑰寫進命令或我會提交的檔案；問我金鑰應從哪裡取得。把它新增到你客戶端的 mcpServers 設定中。
{
"mcpServers": {
"email-deliverability-checker": {
"type": "http",
"url": "https://api.ownmailserver.com/tools/mcp"
}
}
}An MCP server that lets Claude (or any MCP client) diagnose email deliverability:
check_domain: SPF (including the 10-DNS-lookup limit), DMARC policy and reporting, DKIM keys on common selectors, and MX records, with a ranked list of problems and the fix for each. It also names the email services a domain uses (Google Workspace, SendGrid, Amazon SES and others).check_sending_ip: reverse DNS (PTR) and whether it resolves back to the IP, plus listings on Spamhaus ZEN, Barracuda, SpamCop, PSBL, Mailspike and UCEPROTECT level 1.check_email_headers: paste a received message's headers and check them against Gmail's and Yahoo's sender requirements: SPF, DKIM, DMARC, From alignment, one-click unsubscribe (and whether DKIM covers it), TLS, reverse DNS and Message-ID.Every tool is read-only: it reads public DNS or the text you give it. Nothing is sent anywhere else, and no account or API key is needed.
A hosted copy runs at:
Add it to Claude as a custom connector (Settings → Connectors → Add custom connector), or in Claude Code:
It's free and needs no account. It's rate-limited per IP, uses public DNS resolvers (so Spamhaus results show as "refused"; see below), and stores nothing. For heavy use or a real Spamhaus answer, run your own copy.
Requires Node.js 20 or later.
Claude Code
Claude Desktop (claude_desktop_config.json)
Docker
BLOCKLIST_DNS mattersSpamhaus refuses queries that arrive through big public resolvers (8.8.8.8, 1.1.1.1 and the like) and answers 127.255.255.x instead. Many blocklist checkers misread that as "listed". This server reports it as refused, meaning unknown, and says so. To get a real Spamhaus answer, point BLOCKLIST_DNS at a recursive resolver of your own, such as unbound on 127.0.0.1.
include: and redirect= recursively and count every include, a, mx, ptr, exists and redirect term, as RFC 7208 does. More than 10 is a permanent error at most receivers.dkim_selectors (find it in the s= value of a message's DKIM-Signature header). Domains that answer every name (wildcard DNS) are detected and not reported as having keys.Authentication-Results header, which is what the recipient's mailbox provider concluded, and the newest Received hop that names the sending server.example.co.uk). It's not a full Public Suffix List lookup, so unusual suffixes may be misjudged.Built by OwnMailServer, which runs dedicated email sending for businesses that send 250,000 to 1,000,000 emails a month: your own server and IP, a Resend-style API and SMTP, managed warm-up and daily monitoring. OwnMailServer accounts also get a Claude connector for their own sending data: delivery stats, bounces, complaints and message history.
The same checks are available as free web tools: the email health checker and the bulk sender checker.
MIT
來源：README.md，提交 5981484
Check a domain's email DNS
Check a domain's SPF (including the 10-DNS-lookup limit), DMARC policy and reporting, DKIM keys on common selectors, and MX records. Returns problems ranked by severity with the fix for each, plus the email services the domain uses.
domain必填dkim_selectorsCheck a sending IP
Check a mail server's IP: reverse DNS (PTR) and whether it resolves back to the IP, and listings on Spamhaus ZEN, Barracuda, SpamCop, PSBL, Mailspike and UCEPROTECT level 1. A refused Spamhaus query is reported as unknown, never as a listing.
ip必填Check email headers
Check a received email's headers against Gmail's and Yahoo's bulk sender requirements: SPF, DKIM and DMARC results, From domain alignment, one-click unsubscribe (and whether DKIM covers it), TLS, reverse DNS and Message-ID. Use the full headers as the recipient got them (Gmail: Show original).
headers必填已滿足適用檢查項的 100%
該評分衡量此收錄條目的完整程度，依據註冊中心條目、端點與公開來源計算得出。它不是對伺服器本身的評價，也不表示伺服器安全或目前可用：可連通性是帶日期的檢查結果，評分也不包含安裝量或使用者評價。
https://api.ownmailserver.com/tools/mcpclaude mcp add --transport http email-deliverability https://api.ownmailserver.com/tools/mcpclaude mcp add email-deliverability -- npx -y email-deliverability-mcp{ "mcpServers": { "email-deliverability": { "command": "npx", "args": ["-y", "email-deliverability-mcp"] } }}docker build -t email-deliverability-mcp .docker run -i --rm email-deliverability-mcpnpm installnpm test # unit tests with a fake DNS resolvernpm run build # compiles to dist/npm run start:http # the HTTP version (PORT, MCP_PATH, TRUST_PROXY, RATE_LIMIT, GLOBAL_LIMIT)