Domain Mail Check
app.openkrill/mailcheck
About Domain Mail Check
Domain Mail Check is an MCP server published by openkrill.app. Check a domain's email DNS, whether Gmail and Outlook accept its mail, and its registration.
It is hosted by the publisher at one address, so there is nothing to install: your AI client connects to it over the internet.
It asks for no keys or passwords.
Version 1.4.0 was published on 21 October 2026, and the source code is public, so you can read it before installing.
Written from the registry entry. 7 automated checks on the registry entry and the live tool descriptions: 4 pass, 0 warn, 0 fail, 3 info. How we check.
What it asks for
This server declares no environment variables, so it asks for no keys or settings.
Checks
| Check | Result | Detail |
|---|---|---|
| Source repository linked | Pass | https://github.com/nguyenhieuec/agent-tools-plugins |
| Remote uses HTTPS | Pass | All remote endpoints use https:// |
| Secrets requested | Info | Asks for no secrets |
| Namespace ownership | Info | Name verified via domain openkrill.app |
| Registry text aimed at the AI | Pass | Description and settings contain no hidden characters or instructions to the AI |
| Tool descriptions read | Info | Lists 7 tools: launch_score, delivery_check, check_email_auth, check_dns_records, lookup_domain_registration, submit_feedback, get_feedback_reply |
| Hidden instructions in tools | Pass | Read every tool description and the server instructions: no hidden characters or instructions to the AI |
Popularity & health: 50 / 100
Worked out from public numbers and our own checks, not from user reviews or ratings. It says how used and how looked-after a server is, not whether it is safe.
0 forks, 0 merged pull requests. Sources: GitHub, npm, PyPI (pypistats.org) and Hacker News (Algolia), fetched 2026-10-31.
What people say
No Hacker News threads link to its source code.
Look further: search Reddit, search Hacker News, read its GitHub issues. These are not reviews we checked.
Facts
| Registry name | app.openkrill/mailcheck |
|---|---|
| Publisher | Domain openkrill.app |
| How the name is verified | Name verified via domain openkrill.app. The registry ties the name prefix to that account or domain; it does not check the code. |
| Type | Remote: hosted at a URL, nothing to install |
| Remote endpoints | streamable-http https://mailcheck.openkrill.app/mcp |
| Version | 1.4.0 |
| Published | |
| Last updated | |
| Source repository | https://github.com/nguyenhieuec/agent-tools-plugins |
| Website | https://tools.openkrill.app/ |
| Category | Email & messaging (assigned by keyword rule, not by hand) |
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