DemiSignal

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com.demisignal/mcpv1.0.0 Domain verified

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

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check_domain Read-only

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.

domainstring, required

The domain to check, like example.com. A URL or www. host is reduced to the domain.

refreshboolean

Look the DNS up again instead of answering from a check made in the last few minutes, e.g. right after publishing a record. Only once the earlier answer is a minute old.

Tools (3)

check_domain

read-only

Argument	Type	Description
domain*	string	The domain to check, like example.com. A URL or www. host is reduced to the domain.
refresh	boolean	Look the DNS up again instead of answering from a check made in the last few minutes, e.g. right after publishing a record. Only once the earlier answer is a minute old.

Input schema (JSON)

{
  "type": "object",
  "required": [
    "domain"
  ],
  "properties": {
    "domain": {
      "type": "string",
      "maxLength": 253,
      "description": "The domain to check, like example.com. A URL or www. host is reduced to the domain."
    },
    "refresh": {
      "type": "boolean",
      "description": "Look the DNS up again instead of answering from a check made in the last few minutes, e.g. right after publishing a record. Only once the earlier answer is a minute old."
    }
  }
}

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.

read-only

Argument	Type	Description
domain	string	The domain the record protects, like example.com. Used for the host name and the external reporting check.
policy	string	What receivers do with failing email. Start at none while you read reports.
strict_spf	boolean	Require an exact SPF domain match (aspf=s).
strict_dkim	boolean	Require an exact DKIM domain match (adkim=s).
report_addresses	array	Addresses that receive aggregate reports (rua=).
subdomain_policy	string	A different policy for subdomains (sp=). Leave out to use the main policy.

Input schema (JSON)

{
  "type": "object",
  "properties": {
    "domain": {
      "type": "string",
      "maxLength": 253,
      "description": "The domain the record protects, like example.com. Used for the host name and the external reporting check."
    },
    "policy": {
      "enum": [
        "none",
        "quarantine",
        "reject"
      ],
      "type": "string",
      "default": "none",
      "description": "What receivers do with failing email. Start at none while you read reports."
    },
    "strict_spf": {
      "type": "boolean",
      "description": "Require an exact SPF domain match (aspf=s)."
    },
    "strict_dkim": {
      "type": "boolean",
      "description": "Require an exact DKIM domain match (adkim=s)."
    },
    "report_addresses": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "maxItems": 5,
      "description": "Addresses that receive aggregate reports (rua=)."
    },
    "subdomain_policy": {
      "enum": [
        "none",
        "quarantine",
        "reject"
      ],
      "type": "string",
      "description": "A different policy for subdomains (sp=). Leave out to use the main policy."
    }
  }
}

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.

read-only

Argument	Type	Description
a	boolean	The domain's own A record sends email.
mx	boolean	The domain's MX servers send email.
ip4	array	IPv4 addresses or ranges that send, like 192.0.2.10 or 192.0.2.0/24.
ip6	array	IPv6 addresses or ranges that send, like 2001:db8::/32.
includes	array	Other include: domains, like _spf.example.com.
services	array	Email services that send for the domain; each adds its documented include.
hard_fail	boolean	End with -all instead of the usual ~all.

Input schema (JSON)

{
  "type": "object",
  "properties": {
    "a": {
      "type": "boolean",
      "description": "The domain's own A record sends email."
    },
    "mx": {
      "type": "boolean",
      "description": "The domain's MX servers send email."
    },
    "ip4": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "maxItems": 20,
      "description": "IPv4 addresses or ranges that send, like 192.0.2.10 or 192.0.2.0/24."
    },
    "ip6": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "maxItems": 20,
      "description": "IPv6 addresses or ranges that send, like 2001:db8::/32."
    },
    "includes": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "maxItems": 10,
      "description": "Other include: domains, like _spf.example.com."
    },
    "services": {
      "type": "array",
      "items": {
        "enum": [
          "google",
          "microsoft",
          "amazonses",
          "sendgrid",
          "mailgun",
          "postmark",
          "mandrill",
          "brevo",
          "salesforce",
          "zendesk",
          "freshdesk",
          "proton",
          "fastmail"
        ],
        "type": "string"
      },
      "maxItems": 13,
      "description": "Email services that send for the domain; each adds its documented include."
    },
    "hard_fail": {
      "type": "boolean",
      "description": "End with -all instead of the usual ~all."
    }
  }
}