Email deliverability checks: SPF, DKIM, DMARC, BIMI, MTA-STS, blacklists, headers, spam words
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Parse raw email headers: the Received delivery path with per-hop delays, the receiving server's SPF/DKIM/DMARC verdicts, DMARC alignment of the From domain, DKIM signatures, the sending IP, and bulk-sender requirements such as one-click unsubscribe.
The raw header block (everything above the message body).
Parse raw email headers: the Received delivery path with per-hop delays, the receiving server's SPF/DKIM/DMARC verdicts, DMARC alignment of the From domain, DKIM signatures, the sending IP, and bulk-sender requirements such as one-click unsubscribe.
| Argument | Type | Description |
|---|---|---|
| headers* | string | The raw header block (everything above the message body). |
{
"type": "object",
"required": [
"headers"
],
"properties": {
"headers": {
"type": "string",
"description": "The raw header block (everything above the message body)."
}
},
"additionalProperties": false
}Check an IPv4 address against about 18 IP blacklists (SpamCop, Barracuda, UCEPROTECT, PSBL, Mailspike, ...) or a domain against domain blacklists. Each list is verified with its test entries first, so lists that refuse public resolvers (such as Spamhaus) are reported as unavailable rather than clean.
| Argument | Type | Description |
|---|---|---|
| target* | string | IPv4 address or domain. |
{
"type": "object",
"required": [
"target"
],
"properties": {
"target": {
"type": "string",
"description": "IPv4 address or domain."
}
},
"additionalProperties": false
}Run every email-authentication check on a domain (SPF, DKIM, DMARC, MX, MTA-STS, TLS-RPT, BIMI, plus domain and mail-server blacklists) and return a score out of 100, per-check findings and a prioritized fix list. Use this first when asked whether a domain is set up correctly to send email.
| Argument | Type | Description |
|---|---|---|
| domain* | string | Domain name, e.g. example.com. URLs and email addresses are accepted; the domain part is used. |
| dkim_selector | string | DKIM selector (the s= value from a DKIM-Signature header). Optional; common selectors are tried when omitted. |
{
"type": "object",
"required": [
"domain"
],
"properties": {
"domain": {
"type": "string",
"description": "Domain name, e.g. example.com. URLs and email addresses are accepted; the domain part is used."
},
"dkim_selector": {
"type": "string",
"description": "DKIM selector (the s= value from a DKIM-Signature header). Optional; common selectors are tried when omitted."
}
},
"additionalProperties": false
}Look up and validate a single email DNS record for a domain, explaining each tag. record is one of spf, dmarc, dkim, bimi, mta-sts, tls-rpt, mx. SPF counts the 10-lookup limit; DMARC checks policy, reporting and external report authorization; DKIM sizes the key; MTA-STS fetches the policy file and compares it with the MX hosts; BIMI checks the logo (SVG Tiny PS) and mark certificate.
| Argument | Type | Description |
|---|---|---|
| domain* | string | Domain name, e.g. example.com. URLs and email addresses are accepted; the domain part is used. |
| policy | string | MTA-STS only: policy file text to check instead of fetching it. Optional. |
| record* | string | |
| selector | string | DKIM or BIMI selector. Optional. |
{
"type": "object",
"required": [
"domain",
"record"
],
"properties": {
"domain": {
"type": "string",
"description": "Domain name, e.g. example.com. URLs and email addresses are accepted; the domain part is used."
},
"policy": {
"type": "string",
"description": "MTA-STS only: policy file text to check instead of fetching it. Optional."
},
"record": {
"enum": [
"spf",
"dmarc",
"dkim",
"bimi",
"mta-sts",
"tls-rpt",
"mx"
],
"type": "string"
},
"selector": {
"type": "string",
"description": "DKIM or BIMI selector. Optional."
}
},
"additionalProperties": false
}Scan an email subject and body (plain text or HTML) for spam-trigger phrases by category, ALL-CAPS, exclamation runs, emoji, URL shorteners and image-heavy HTML. Returns a low/medium/high risk reading and, optionally, a rule-based rewrite.
| Argument | Type | Description |
|---|---|---|
| body | string | Plain text or HTML. |
| rewrite | boolean | Also return a calmer rewrite of the subject (and of a plain-text body). |
| subject | string |
{
"type": "object",
"properties": {
"body": {
"type": "string",
"description": "Plain text or HTML."
},
"rewrite": {
"type": "boolean",
"description": "Also return a calmer rewrite of the subject (and of a plain-text body)."
},
"subject": {
"type": "string"
}
},
"additionalProperties": false
}