MCP server · DemiSignal

DemiSignal MCP Server

Email authentication tools for a domain. check_domain looks up the domain's live DNS and grades its DMARC, SPF, DKIM, MX, BIMI and MTA-STS records. generate_spf_record and generate_dmarc_record build a record from your answers without looking anything up.

Open endpoint → DemiSignal provider profile

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Provider: DemiSignal Type: Hosted endpoint Transport: Host: demisignal.com

Endpoint

https://demisignal.com/mcp

Hosted endpoint · transport

Connect

This is a remote MCP server — point an MCP client at the endpoint URL. Clients with native remote support (Claude, Cursor, VS Code, …):

# mcp client config (e.g. .mcp.json / mcp settings) { "mcpServers": { "demisignal-com": { "url": "https://demisignal.com/mcp" } } }

For stdio-only clients (older Claude Desktop, etc.), bridge with mcp-remote:

# Add to claude_desktop_config.json { "mcpServers": { "demisignal-com": { "command": "npx", "args": ["-y", "mcp-remote", "https://demisignal.com/mcp"] } } }

If the server requires authentication, add the provider's token/header (e.g. an X-API-Key) per its docs. A quick reachability check:

curl -i -X POST https://demisignal.com/mcp \ -H "Content-Type: application/json" -H "Accept: application/json, text/event-stream" \ -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

Tools

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.
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.
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.

About MCP

The Model Context Protocol (MCP) is an open protocol Anthropic introduced for connecting LLM-based agents to external tools and data sources. Providers publish MCP servers that expose their API surface as structured, discoverable tools — an MCP-compatible client (Claude Desktop, Cursor, Cline, Continue, etc.) can connect to the server and call its tools without any per-provider integration code.

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MCP server

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https://apis.io/mcp

Tools for mcp servers

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curl "https://apis.io/api/v1/mcp/demisignal-mcp-server"

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