DemiSignal MCP Server

by demisignal Your server? Claim it

answering

DemiSignal is answering right now. Last checked 7 min ago. It exposes 3 tools.

Check a domain's DMARC, SPF, DKIM, MX, BIMI and MTA-STS records. Generate SPF and DMARC records.

Uptime history 28 days of history · worst day 99%

28 days agonow

100.0%

Uptime 24h

91 of 91 checks

Tools

read from the server

836 ms

Response time

average over 24h

open, no key

Access

streamable-http

What changed 2

Every tool that appeared, vanished or quietly changed what it asks for. Recorded since 23 October 2026. No other catalogue keeps this.

23 Oct a tool description was rewritten check_domain

23 Oct a tool changed the parameters it asks for check_domain

DemiSignal missed one check this week

Everything else answered, so this is steady rather than shaky. We check every 15 minutes, which is how a one-off gets told apart from the start of a pattern, and how you hear about the next one within the hour instead of from your users.

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 7 min ago.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add mcp --transport http 'https://demisignal.com/mcp?utm_source=mcp-registry'

Settings → Connectors → Add custom connector, then paste this address

https://demisignal.com/mcp?utm_source=mcp-registry

~/.codex/config.toml

[mcp_servers.mcp]
url = "https://demisignal.com/mcp?utm_source=mcp-registry"

.cursor/mcp.json

{
  "mcpServers": {
    "mcp": {
      "url": "https://demisignal.com/mcp?utm_source=mcp-registry"
    }
  }
}

.vscode/mcp.json

{
  "servers": {
    "mcp": {
      "type": "http",
      "url": "https://demisignal.com/mcp?utm_source=mcp-registry"
    }
  }
}

Available tools 3

Read directly from the server with tools/list, grouped by what they act on. If a tool disappears, we record the date.

generate

generate_dmarc_record

Build a DMARC TXT record and the host to publish it at, from a policy and the addresses that should receive aggregate reports. Notes what the record does not cover yet. Computes from the arguments only; nothing is looked up or stored.

generate_spf_record

Build an SPF TXT record from the services and servers that send email for a domain, with an estimate of the DNS lookups it uses against SPF's limit of 10. Computes from the arguments only; nothing is looked up or stored.

domain

check_domain

Look up a domain's live DNS and grade its email authentication: DMARC, SPF, DKIM (common selectors), MX, BIMI and MTA-STS. Returns each record, its status and the issues found, with a guide link per issue. A domain checked in the last few minutes is answered from that check (cached, with its age); pass refresh to look again after changing DNS.

Endpoints

URL	Transport	State	Latency	Checked
https://demisignal.com/mcp?utm_source=mcp-registry	streamable-http	answering	659 ms	7 min ago

Alternatives to DemiSignal

same job, measured the same way

Stamp

by clawhard

Check a domain's SPF, DKIM, DMARC and MX from live DNS, the Gmail/Yahoo rules, and fix records.

2 tools answering

DomainCanary

by domaincanary

Check a domain's DMARC, SPF and DKIM, build SPF records, explain bounces, read DMARC reports.

4 tools answering

MailX Email Deliverability

by themailx

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

17 tools answering

DnsGuard

by workers-mike-tusa-dnsguard

Check a domain's email authentication: SPF, DKIM, DMARC, BIMI, MX, MTA-STS, TLS-RPT. Score + fixes.

1 tools answering

Email Deliverability

by inboxguard

Scan and fix a domain's email deliverability (SPF, DKIM, DMARC, MTA-STS, BIMI, DNS blocklists).

28 tools answering

MX Verdict

by mxverdict

Free, read-only email and DNS checks: SPF, DKIM, DMARC, MX, DNS records, blocklists, domain health.

7 tools answering

TamingDNS

by tamingdns

Check SPF, DKIM, DMARC, MX, MTA-STS, TLS-RPT, BIMI, DANE and DNSSEC, and analyse email headers.

13 tools answering

HostSherlock

by hostsherlock

Check SPF, DKIM, DMARC and MX of any domain, and read the DMARC reports of domains you monitor.

answering

DemiSignal — questions

Answers built from our own checks of this server.

What can DemiSignal do?

It exposes 3 tools, read directly from the server on our last check. Among them: check_domain, generate_dmarc_record, generate_spf_record. The full list with descriptions is on this page — we take it from the server itself via tools/list, not from a README. How MCP servers expose tools in the first place →

Is DemiSignal working right now?

We send a real MCP handshake every 15 minutes. Over the last 24 hours 91 of 91 checks got a reply (100.0%), average response time 836 ms. The bar chart above shows every period we have measured.

How do I connect DemiSignal?

Copy the ready config from this page. We generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each in the form that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address.

Does DemiSignal need an API key?

No. DemiSignal completed a full MCP handshake with us as an anonymous client and listed its tools without asking for anything. All 3 of them are readable on this page. This is what we observed, not what the docs claim.

How fast is DemiSignal?

It answers our handshake in 836 ms on average, which is faster than 8% of all working MCP servers we measure. That is on the slow side — worth knowing if the tool sits inside an interactive loop. The comparison comes from our own checks across the whole registry, every 15 minutes.