DnsGuard
Check a domain's email authentication: SPF, DKIM, DMARC, BIMI, MX, MTA-STS, TLS-RPT. Score + fixes.
Should I use this
Quality & Safety
A
Based on automated analysis of tool definitions and protocol compliance.
Context Cost
~1,692Tokens (tool definitions)
~18.3 KBTypical response size
Moderate attention impact (1.32% of 128k context)
This is the approximate number of tokens consumed each time the server's tools are loaded into a model's context. Higher counts reduce the attention available for other tasks.
Install
One-Click Install
Add this to your `claude_desktop_config.json` file:
{
"mcpServers": {
"dnsguard": {
"url": "https://dnsguard.mike-tusa.workers.dev/mcp"
}
}
}Remote endpoints
https://dnsguard.mike-tusa.workers.dev/mcpstreamable-httpWhat it can do
Tool inventory
Tools (1)
🟢 Read-only🟡 Write🔴 Delete⚪ Unknown
🟢check_domain(domain, dkim_selector, include_raw)
Audit the email-authentication DNS records of a domain. Returns a 0–100 score and A–F grade (MX 10, SPF 25, DMARC 30, DKIM 25, BIMI 10, plus up to 5 bonus points for MTA-STS and TLS-RPT, capped at 100), each check's status, published record, findings and recommended fixes, and a link to the full report. Read-only: it only queries public DNS and the domain's public MTA-STS policy file. Same engine and scoring as the DnsGuard JSON API (GET /api/check).
Input Schema
{
"type": "object",
"properties": {
"domain": {
"type": "string",
"minLength": 1,
"maxLength": 300,
"description": "Domain to check, e.g. example.com. A URL or email address is accepted and reduced to its domain."
},
"dkim_selector": {
"type": "string",
"maxLength": 255,
"description": "Optional DKIM selector (the s= value from a DKIM-Signature header), e.g. s1 or google. Common selectors are always tried."
},
"include_raw": {
"type": "boolean",
"default": false,
"description": "Also return the full /api/check JSON (all records, SPF include tree, DKIM keys) in structuredContent.raw. Larger output."
}
},
"required": [
"domain"
],
"additionalProperties": false
}Output Schema
{
"type": "object",
"properties": {
"domain": {
"type": "string"
},
"organizationalDomain": {
"type": "string"
},
"score": {
"type": "number"
},
"maxScore": {
"type": "number"
},
"grade": {
"type": "string",
"enum": [
"A",
"B",
"C",
"D",
"F"
]
},
"scoreBreakdown": {
"type": "object",
"properties": {
"base": {
"type": "number"
},
"bonus": {
"type": "number"
},
"bonusMax": {
"type": "number"
},
"cap": {
"type": "number"
}
}
},
"checks": {
"type": "object",
"properties": {
"mx": {
"type": "object",
"properties": {
"status": {
"type": "string",
"enum": [
"pass",
"warn",
"fail",
"info"
]
},
"score": {
"type": "number"
},
"maxScore": {
"type": "number"
},
"bonus": {
"type": "boolean",
"description": "true for MTA-STS / TLS-RPT (bonus points on top of the 100-point core)"
},
"record": {
"type": "string",
"description": "Published record (omitted when none was found)"
},
"findings": {
"type": "array",
"items": {
"type": "object",
"properties": {
"level": {
"type": "string",
"enum": [
"pass",
"info",
"warn",
"fail"
]
},
"message": {
"type": "string"
}
},
"required": [
"level",
"message"
]
}
},
"recommendations": {
"type": "array",
"items": {
"type": "string"
}
}
},
"required": [
"status",
"score",
"maxScore",
"findings",
"recommendations"
]
},
"spf": {
"type": "object",
"properties": {
"status": {
"type": "string",
"enum": [
"pass",
"warn",
"fail",
"info"
]
},
"score": {
"type": "number"
},
"maxScore": {
"type": "number"
},
"bonus": {
"type": "boolean",
"description": "true for MTA-STS / TLS-RPT (bonus points on top of the 100-point core)"
},
"record": {
"type": "string",
"description": "Published record (omitted when none was found)"
},
"findings": {
"type": "array",
"items": {
"type": "object",
"properties": {
"level": {
"type": "string",
"enum": [
"pass",
"info",
"warn",
"fail"
]
},
"message": {
"type": "string"
}
},
"required": [
"level",
"message"
]
}
},
"recommendations": {
"type": "array",
"items": {
"type": "string"
}
}
},
"required": [
"status",
"score",
"maxScore",
"findings",
"recommendations"
]
},
"dmarc": {
"type": "object",
"properties": {
"status": {
"type": "string",
"enum": [
"pass",
"warn",
"fail",
"info"
]
},
"score": {
"type": "number"
},
"maxScore": {
"type": "number"
},
"bonus": {
"type": "boolean",
"description": "true for MTA-STS / TLS-RPT (bonus points on top of the 100-point core)"
},
"record": {
"type": "string",
"description": "Published record (omitted when none was found)"
},
"findings": {
"type": "array",
"items": {
"type": "object",
"properties": {
"level": {
"type": "string",
"enum": [
"pass",
"info",
"warn",
"fail"
]
},
"message": {
"type": "string"
}
},
"required": [
"level",
"message"
]
}
},
"recommendations": {
"type": "array",
"items": {
"type": "string"
}
}
},
"required": [
"status",
"score",
"maxScore",
"findings",
"recommendations"
]
},
"dkim": {
"type": "object",
"properties": {
"status": {
"type": "string",
"enum": [
"pass",
"warn",
"fail",
"info"
]
},
"score": {
"type": "number"
},
"maxScore": {
"type": "number"
},
"bonus": {
"type": "boolean",
"description": "true for MTA-STS / TLS-RPT (bonus points on top of the 100-point core)"
},
"record": {
"type": "string",
"description": "Published record (omitted when none was found)"
},
"findings": {
"type": "array",
"items": {
"type": "object",
"properties": {
"level": {
"type": "string",
"enum": [
"pass",
"info",
"warn",
"fail"
]
},
"message": {
"type": "string"
}
},
"required": [
"level",
"message"
]
}
},
"recommendations": {
"type": "array",
"items": {
"type": "string"
}
}
},
"required": [
"status",
"score",
"maxScore",
"findings",
"recommendations"
]
},
"bimi": {
"type": "object",
"properties": {
"status": {
"type": "string",
"enum": [
"pass",
"warn",
"fail",
"info"
]
},
"score": {
"type": "number"
},
"maxScore": {
"type": "number"
},
"bonus": {
"type": "boolean",
"description": "true for MTA-STS / TLS-RPT (bonus points on top of the 100-point core)"
},
"record": {
"type": "string",
"description": "Published record (omitted when none was found)"
},
"findings": {
"type": "array",
"items": {
"type": "object",
"properties": {
"level": {
"type": "string",
"enum": [
"pass",
"info",
"warn",
"fail"
]
},
"message": {
"type": "string"
}
},
"required": [
"level",
"message"
]
}
},
"recommendations": {
"type": "array",
"items": {
"type": "string"
}
}
},
"required": [
"status",
"score",
"maxScore",
"findings",
"recommendations"
]
},
"mtaSts": {
"type": "object",
"properties": {
"status": {
"type": "string",
"enum": [
"pass",
"warn",
"fail",
"info"
]
},
"score": {
"type": "number"
},
"maxScore": {
"type": "number"
},
"bonus": {
"type": "boolean",
"description": "true for MTA-STS / TLS-RPT (bonus points on top of the 100-point core)"
},
"record": {
"type": "string",
"description": "Published record (omitted when none was found)"
},
"findings": {
"type": "array",
"items": {
"type": "object",
"properties": {
"level": {
"type": "string",
"enum": [
"pass",
"info",
"warn",
"fail"
]
},
"message": {
"type": "string"
}
},
"required": [
"level",
"message"
]
}
},
"recommendations": {
"type": "array",
"items": {
"type": "string"
}
}
},
"required": [
"status",
"score",
"maxScore",
"findings",
"recommendations"
]
},
"tlsRpt": {
"type": "object",
"properties": {
"status": {
"type": "string",
"enum": [
"pass",
"warn",
"fail",
"info"
]
},
"score": {
"type": "number"
},
"maxScore": {
"type": "number"
},
"bonus": {
"type": "boolean",
"description": "true for MTA-STS / TLS-RPT (bonus points on top of the 100-point core)"
},
"record": {
"type": "string",
"description": "Published record (omitted when none was found)"
},
"findings": {
"type": "array",
"items": {
"type": "object",
"properties": {
"level": {
"type": "string",
"enum": [
"pass",
"info",
"warn",
"fail"
]
},
"message": {
"type": "string"
}
},
"required": [
"level",
"message"
]
}
},
"recommendations": {
"type": "array",
"items": {
"type": "string"
}
}
},
"required": [
"status",
"score",
"maxScore",
"findings",
"recommendations"
]
}
}
},
"notes": {
"type": "array",
"items": {
"type": "string"
}
},
"checkedAt": {
"type": "string"
},
"cached": {
"type": "boolean"
},
"tier": {
"type": "string",
"enum": [
"anonymous",
"free",
"pro"
]
},
"reportUrl": {
"type": "string"
},
"apiUrl": {
"type": "string"
},
"version": {
"type": "string"
},
"raw": {
"type": "object",
"description": "Full /api/check response (only when include_raw is true)"
}
},
"required": [
"domain",
"score",
"maxScore",
"grade",
"checks",
"reportUrl"
]
}Community
Evidence
Recent observations
verifiedversion not recorded1 tools