← Domains & DNS
domains by fourzerotwo
Email authentication check
MX, SPF and DMARC for a domain, the mail provider, issues found and a grade.
Email authentication check
MX, SPF and DMARC for a domain, the mail provider, issues found and a grade.
- price
- $0.003 / call
- free tier
- 3 free / day
- MCP tool
- domains__email-auth
- method
- GET
GET https://fourzerotwo.si/v1/domains/email-auth
| Param | Type | Description |
|---|---|---|
| domain | string | Domain |
# unpaid: returns 402 with the price curl -i "https://fourzerotwo.si/v1/domains/email-auth?domain=gov.uk" # free tier: send a free key from https://fourzerotwo.si/free curl -H "X-API-Key: fzt_…" "https://fourzerotwo.si/v1/domains/email-auth?domain=gov.uk"
Use it from an AI agent (MCP)
Add the server once, then ask for this data in plain English. The agent finds the endpoint with search_apis and runs it with call_api.
{
"mcpServers": {
"fourzerotwo": { "type": "http", "url": "https://fourzerotwo.si/mcp" }
}
}
# the call the agent makes
call_api {"tool": "domains__email-auth", "arguments": {"domain":"gov.uk"}}
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