Properties
| Name | Type | Description |
|---|---|---|
| tool | string | |
| query | object | The inputs after normalisation. |
| checked_at | string | When the lookups ran, ISO 8601 UTC. |
| duration_ms | integer | |
| status | string | Overall verdict. "error" means the check could not complete (timeout, SERVFAIL); it is never "pass" when a lookup the verdict needs failed. |
| findings | array | |
| signatures_verified | boolean | Always false: there is no body, so DKIM and ARC signatures are read, not verified. Pass and fail come from the receiver's Authentication-Results. |
| summary | object | |
| hops | array | |
| delivery | object | |
| delivering_ip | object | |
| auth | object | |
| alignment | object | |
| dkim_signatures | array | |
| arc | object | |
| list_unsubscribe | object | |
| spam | array | |
| fields | array |
JSON Schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"$id": "https://artifacts.apis.io/email-spam-tester-com/json-schema/email-spam-tester-com-mailtester-api-tools-header-out-schema.json",
"title": "HeaderOut",
"x-generated": "2026-11-06",
"x-method": "derived",
"x-generator": "derive-json-schema.py",
"x-source": "openapi/email-spam-tester-com-openapi.json#/components/schemas/mailtester__api__tools__HeaderOut",
"properties": {
"tool": {
"type": "string",
"title": "Tool"
},
"query": {
"additionalProperties": {
"type": "string"
},
"type": "object",
"title": "Query",
"description": "The inputs after normalisation."
},
"checked_at": {
"type": "string",
"title": "Checked At",
"description": "When the lookups ran, ISO 8601 UTC."
},
"duration_ms": {
"type": "integer",
"title": "Duration Ms"
},
"status": {
"type": "string",
"enum": [
"pass",
"warn",
"fail",
"error"
],
"title": "Status",
"description": "Overall verdict. \"error\" means the check could not complete (timeout, SERVFAIL); it is never \"pass\" when a lookup the verdict needs failed."
},
"findings": {
"items": {
"$ref": "#/$defs/Finding"
},
"type": "array",
"title": "Findings"
},
"signatures_verified": {
"type": "boolean",
"title": "Signatures Verified",
"description": "Always false: there is no body, so DKIM and ARC signatures are read, not verified. Pass and fail come from the receiver's Authentication-Results."
},
"summary": {
"$ref": "#/$defs/HeaderSummary"
},
"hops": {
"items": {
"$ref": "#/$defs/HeaderHop"
},
"type": "array",
"title": "Hops"
},
"delivery": {
"$ref": "#/$defs/HeaderDelivery"
},
"delivering_ip": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Delivering Ip"
},
"auth": {
"$ref": "#/$defs/HeaderAuth"
},
"alignment": {
"$ref": "#/$defs/HeaderAlignment"
},
"dkim_signatures": {
"items": {
"$ref": "#/$defs/DkimSignature"
},
"type": "array",
"title": "Dkim Signatures"
},
"arc": {
"$ref": "#/$defs/HeaderArc"
},
"list_unsubscribe": {
"$ref": "#/$defs/HeaderUnsubscribe"
},
"spam": {
"items": {
"$ref": "#/$defs/SpamHeader"
},
"type": "array",
"title": "Spam"
},
"fields": {
"items": {
"$ref": "#/$defs/HeaderField"
},
"type": "array",
"title": "Fields"
}
},
"type": "object",
"required": [
"tool",
"query",
"checked_at",
"duration_ms",
"status",
"findings",
"signatures_verified",
"summary",
"hops",
"delivery",
"delivering_ip",
"auth",
"alignment",
"dkim_signatures",
"arc",
"list_unsubscribe",
"spam",
"fields"
],
"$defs": {
"AlignedDkim": {
"properties": {
"d": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "D"
},
"s": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "S"
},
"verified": {
"anyOf": [
{
"type": "boolean"
},
{
"type": "null"
}
],
"title": "Verified",
"description": "From the receiver's verdict; null when it says nothing about this signature."
},
"aligned": {
"anyOf": [
{
"type": "string",
"enum": [
"strict",
"relaxed"
]
},
{
"type": "null"
}
],
"title": "Aligned"
}
},
"type": "object",
"required": [
"d",
"s",
"verified",
"aligned"
],
"title": "AlignedDkim"
},
"AlignedDmarc": {
"properties": {
"result": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Result"
},
"policy": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Policy"
},
"disposition": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Disposition"
}
},
"type": "object",
"required": [
"result",
"policy",
"disposition"
],
"title": "AlignedDmarc"
},
"AlignedSpf": {
"properties": {
"domain": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Domain"
},
"result": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Result"
},
"aligned": {
"anyOf": [
{
"type": "string",
"enum": [
"strict",
"relaxed"
]
},
{
"type": "null"
}
],
"title": "Aligned"
}
},
"type": "object",
"required": [
"domain",
"result",
"aligned"
],
"title": "AlignedSpf"
},
"ArcSet": {
"properties": {
"i": {
"type": "integer",
"title": "I"
},
"cv": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Cv"
},
"seal_d": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Seal D"
},
"seal_s": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Seal S"
},
"ams_d": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Ams D"
},
"ams_s": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Ams S"
},
"authserv_id": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Authserv Id"
}
},
"type": "object",
"required": [
"i",
"cv",
"seal_d",
"seal_s",
"ams_d",
"ams_s",
"authserv_id"
],
"title": "ArcSet"
},
"AuthOther": {
"properties": {
"authserv_id": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Authserv Id"
},
"results": {
"items": {
"$ref": "#/$defs/AuthResult"
},
"type": "array",
"title": "Results"
},
"header": {
"type": "string",
"title": "Header"
}
},
"type": "object",
"required": [
"authserv_id",
"results",
"header"
],
"title": "AuthOther"
},
"AuthResult": {
"properties": {
"method": {
"type": "string",
"title": "Method"
},
"result": {
"type": "string",
"title": "Result"
},
"reason": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Reason"
},
"props": {
"additionalProperties": {
"type": "string"
},
"type": "object",
"title": "Props"
},
"comment": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Comment"
}
},
"type": "object",
"required": [
"method",
"result",
"reason",
"props",
"comment"
],
"title": "AuthResult"
},
"AuthResults": {
"properties": {
"authserv_id": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Authserv Id"
},
"results": {
"items": {
"$ref": "#/$defs/AuthResult"
},
"type": "array",
"title": "Results"
}
},
"type": "object",
"required": [
"authserv_id",
"results"
],
"title": "AuthResults"
},
"DkimSignature": {
"properties": {
"d": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "D"
},
"s": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "S"
},
"a": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "A"
},
"c": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "C"
},
"h": {
"items": {
"type": "string"
},
"type": "array",
"title": "H"
},
"l": {
"anyOf": [
{
"type": "integer"
},
{
"type": "null"
}
],
"title": "L"
},
"t": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "T"
},
"x": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "X"
},
"i": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "I"
}
},
"type": "object",
"required": [
"d",
"s",
"a",
"c",
"h",
"l",
"t",
"x",
"i"
],
"title": "DkimSignature"
},
"Finding": {
"properties": {
"code": {
"type": "string",
"title": "Code",
"description": "Stable identifier, e.g. spf.too_many_lookups. The English template for every code is in /i18n/tools/findings.en.json on the website."
},
"level": {
"type": "string",
"enum": [
"pass",
"info",
"warn",
"fail",
"error"
],
"title": "Level"
},
"params": {
"additionalProperties": true,
"type": "object",
"title": "Params",
"description": "Values the message is built from."
},
"message": {
"type": "string",
"title": "Message",
"description": "The English sentence, params filled in."
}
},
"type": "object",
"required": [
"code",
"level",
"params",
"message"
],
"title": "Finding"
},
"HeaderAlignment": {
"properties": {
"from_domain": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "From Domain"
},
"dkim": {
"items": {
"$ref": "#/$defs/AlignedDkim"
},
"type": "array",
"title": "Dkim"
},
"spf": {
"$ref": "#/$defs/AlignedSpf"
},
"dmarc": {
"$ref": "#/$defs/AlignedDmarc"
}
},
"type": "object",
"required": [
"from_domain",
"dkim",
"spf",
"dmarc"
],
"title": "HeaderAlignment"
},
"HeaderArc": {
"properties": {
"instances": {
"type": "integer",
"title": "Instances"
},
"valid_structure": {
"anyOf": [
{
"type": "boolean"
},
{
"type": "null"
}
],
"title": "Valid Structure",
"description": "Numbering, completeness and cv= only; no signature is verified."
},
"sets": {
"items": {
"$ref": "#/$defs/ArcSet"
},
"type": "array",
"title": "Sets"
}
},
"type": "object",
"required": [
"instances",
"valid_structure",
"sets"
],
"title": "HeaderArc"
},
"HeaderAuth": {
"properties": {
"verdict": {
"anyOf": [
{
"$ref": "#/$defs/AuthResults"
},
{
"type": "null"
}
],
"description": "The topmost Authentication-Results: the receiver's own."
},
"other": {
"items": {
"$ref": "#/$defs/AuthOther"
},
"type": "array",
"title": "Other",
"description": "Every other Authentication-Results, written before the receiver and not to be trusted."
}
},
"type": "object",
"required": [
"verdict",
"other"
],
"title": "HeaderAuth"
},
"HeaderDelivery": {
"properties": {
"first": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "First"
},
"last": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Last"
},
"total_s": {
"anyOf": [
{
"type": "integer"
},
{
"type": "null"
}
],
"title": "Total S"
},
"date_skew_s": {
"anyOf": [
{
"type": "integer"
},
{
"type": "null"
}
],
"title": "Date Skew S",
"description": "First Received time minus the Date header."
},
"hops": {
"type": "integer",
"title": "Hops"
}
},
"type": "object",
"required": [
"first",
"last",
"total_s",
"date_skew_s",
"hops"
],
"title": "HeaderDelivery"
},
"HeaderField": {
"properties": {
"name": {
"type": "string",
"title": "Name"
},
"value": {
"type": "string",
"title": "Value"
}
},
"type": "object",
"required": [
"name",
"value"
],
"title": "HeaderField"
},
"HeaderHop": {
"properties": {
"index": {
"type": "integer",
"title": "Index",
"description": "1 is the oldest hop: the list runs from the sender to the receiver."
},
"from_host": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "From Host"
},
"from_rdns": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "From Rdns"
},
"from_ip": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "From Ip"
},
"by_host": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "By Host"
},
"with": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "With"
},
"id": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Id"
},
"for": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "For"
},
"tls": {
"anyOf": [
{
"type": "boolean"
},
{
"type": "null"
}
],
"title": "Tls",
"description": "null for hops inside one provider, where the header says nothing either way."
},
"tls_detail": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Tls Detail"
},
"timestamp": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Timestamp"
},
"delay_s": {
"anyOf": [
{
"type": "integer"
},
{
"type": "null"
}
],
"title": "Delay S",
"description": "Seconds since the previous hop's timestamp; Received dates have one-second precision."
},
"clock_skew": {
"type": "boolean",
"title": "Clock Skew"
},
"raw": {
"type": "string",
"title": "Raw"
}
},
"type": "object",
"required": [
"index",
"from_host",
"from_rdns",
"from_ip",
"by_host",
"with",
"id",
"for",
"tls",
"tls_detail",
"timestamp",
"delay_s",
"clock_skew",
"raw"
],
"title": "HeaderHop"
},
"HeaderSummary": {
"properties": {
"from": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "From"
},
"from_name": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "From Name"
},
"from_domain": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "From Domain"
},
"return_path": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Return Path"
},
"return_path_domain": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Return Path Domain"
},
"to": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "To"
},
"subject": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Subject",
"description": "MIME encoded-words decoded."
},
"date": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Date",
"description": "The Date header, ISO 8601 UTC."
},
"message_id": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Message Id"
},
"message_id_domain": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Message Id Domain"
}
},
"type": "object",
"required": [
"from",
"from_name",
"from_domain",
"return_path",
"return_path_domain",
"to",
"subject",
"date",
"message_id",
"message_id_domain"
],
"title": "HeaderSummary"
},
"HeaderUnsubscribe": {
"properties": {
"present": {
"type": "boolean",
"title": "Present"
},
"https": {
"type": "boolean",
"title": "Https"
},
"mailto": {
"type": "boolean",
"title": "Mailto"
},
"one_click": {
"type": "boolean",
"title": "One Click"
},
"signed": {
"anyOf": [
{
"type": "boolean"
},
{
"type": "null"
}
],
"title": "Signed",
"description": "Listed in h= of one DKIM signature (with List-Unsubscribe-Post when present)."
}
},
"type": "object",
"required": [
"present",
"https",
"mailto",
"one_click",
"signed"
],
"title": "HeaderUnsubscribe"
},
"SpamHeader": {
"properties": {
"header": {
"type": "string",
"title": "Header"
},
"engine": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"title": "Engine"
},
"flag": {
"anyOf": [
{
"type": "boolean"
},
{
"type": "null"
}
],
"title": "Flag"
},
"score": {
"anyOf": [
{
"type": "number"
},
{
"type": "null"
}
],
"title": "Score"
},
"threshold": {
"anyOf": [
{
"type": "number"
},
{
"type": "null"
}
],
"title": "Threshold"
},
"value": {
"type": "string",
"title": "Value"
}
},
"type": "object",
"required": [
"header",
"engine",
"flag",
"score",
"threshold",
"value"
],
"title": "SpamHeader"
}
}
}Work with this as data
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