{ "openapi": "3.1.1", "info": { "title": "E-mail Infrastructure Explorer API", "version": "1.0.0", "summary": "MX, SPF lookups, DMARC, DKIM, MTA-STS, TLS-RPT and BIMI for a domain, scored with fixes.", "description": "Every endpoint performs the same calculation as the human page and returns inputs, result, units, assumptions, sources, warnings and computedAt. MCP endpoint: /mcp." }, "servers": [ { "url": "https://emailinfrastructureexplorer.usefulweb.site" } ], "paths": { "/api/v1/calculate": { "post": { "operationId": "calculate", "summary": "MX, SPF lookups, DMARC, DKIM, MTA-STS, TLS-RPT and BIMI for a domain, scored with fixes.", "description": "Checks how a domain receives and protects e-mail: MX hosts with priorities and addresses, SPF with a recursive DNS-lookup count across include: chains, DMARC policy and reporting, DKIM keys at ten common selectors, MTA-STS record and policy file, TLS-RPT and BIMI. Produces a transparent 100-point score and concrete DNS fixes. Works live or on pasted zone records.\n\nMethodology:\n- DNS: MX (+ A/AAAA of each exchange), TXT at the domain, _dmarc, ._domainkey for default, google, selector1, selector2, k1, s1, s2, mail, dkim, mx, _mta-sts, _smtp._tls and default._bimi.\n- SPF (RFC 7208): include: and redirect= are followed recursively; include, a, mx, ptr, exists and redirect each cost one DNS lookup, more than 10 in total is a permerror; more than 2 void lookups is also an error.\n- DMARC (RFC 7489) policy, pct and rua. DKIM (RFC 6376): key type and RSA modulus length decoded from p=; empty p= means revoked. Real selectors are chosen by the sender and cannot be enumerated, so \"none found\" is not proof that DKIM is absent.\n- MTA-STS (RFC 8461): TXT v=STSv1 plus the policy at https://mta-sts./.well-known/mta-sts.txt; each MX must match a policy mx: pattern. TLS-RPT (RFC 8460) v=TLSRPTv1 with rua. BIMI needs DMARC quarantine/reject at 100 %.\n- Score (100): MX 10, SPF 20, DMARC 25, DKIM 15, MTA-STS 15, TLS-RPT 10, BIMI 5. Domains with a null MX (no inbound mail) are scored only on SPF and DMARC, scaled to 100.", "tags": [ "infrastructure" ], "x-mcp-tool": "email_infrastructure_explorer", "requestBody": { "required": true, "content": { "application/json": { "schema": { "$ref": "#/components/schemas/EmailInfrastructureExplorerInput" }, "examples": { "example1": { "summary": "Pasted records for a typical business domain", "value": { "mode": "paste", "domain": "example.org", "records": "; pasted DNS for example.org\n@ MX 10 mx1.example.net.\n@ MX 20 mx2.example.net.\nmx1.example.net. A 192.0.2.10\nmx2.example.net. A 192.0.2.20\n@ TXT \"v=spf1 include:_spf.example.net include:sendgrid.net ip4:198.51.100.0/24 ~all\"\n_spf.example.net. TXT \"v=spf1 ip4:192.0.2.0/24 include:_spf2.example.net -all\"\n_spf2.example.net. TXT \"v=spf1 a mx -all\"\n_dmarc TXT \"v=DMARC1; p=quarantine; pct=100; rua=mailto:dmarc@example.org\"\nselector1._domainkey TXT \"v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvO65ahmEjafCxJBT+BnCuE+pM97kMp7njI4Na2g3vJ3AIqbUS2lTQVRlUng5T7BKOAHVmKUnj2fWM+iRt5mQAZ649dKjdQwOPULKmoVMjGMH8SB3P6CYaxJrVgS+PGVtEFgcj8UADfED2ylfiZgAPw7Fx3PQxyfWbenvdEsLyjSyl/2fr/stYzeGvaRDjKd91UoPqZEBC3fyw5Eloyq5L/U2yCSJypPpFe04kC6i4OcIlx6bJUkJWMaodPyFd3x1wuS9jklXaF+yyZhBMIdQzNCyf20QM4lf/SjmyzMsyYs5ILkH4548cgWHuM+wGdGHf5GwI6dTFv0a90bL3hlLdQIDAQAB\"\n_mta-sts TXT \"v=STSv1; id=20261001T000000\"\n_smtp._tls TXT \"v=TLSRPTv1; rua=mailto:tlsrpt@example.org\"", "mtaStsPolicy": "version: STSv1\nmode: testing\nmx: mx1.example.net\nmx: *.example.net\nmax_age: 604800" } } } } } }, "responses": { "200": { "description": "Calculation result envelope.", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/EmailInfrastructureExplorerResult" } } } }, "400": { "description": "Malformed JSON body.", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "422": { "description": "Invalid input (see errors[]).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } }, "429": { "description": "Rate limit exceeded (see Retry-After).", "content": { "application/problem+json": { "schema": { "$ref": "#/components/schemas/Problem" } } } } } } }, "/api/v1/tool": { "get": { "operationId": "getToolDefinition", "summary": "Inputs, output schema and examples for this tool", "responses": { "200": { "description": "Tool definition.", "content": { "application/json": { "schema": { "type": "object" } } } } } } } }, "components": { "schemas": { "Problem": { "type": "object", "description": "RFC 9457 problem details. 422 responses include per-field `errors`.", "required": [ "type", "title", "status", "detail" ], "properties": { "type": { "type": "string" }, "title": { "type": "string" }, "status": { "type": "integer" }, "detail": { "type": "string" }, "code": { "type": "string" }, "errors": { "type": "array", "items": { "type": "object", "required": [ "field", "message" ], "properties": { "field": { "type": "string" }, "message": { "type": "string" } } } } } }, "EmailInfrastructureExplorerInput": { "type": "object", "additionalProperties": false, "properties": { "mode": { "title": "Mode", "type": "string", "enum": [ "live", "paste" ], "default": "live" }, "domain": { "title": "Domain", "type": "string", "maxLength": 253 }, "records": { "title": "DNS records (paste mode)", "description": "Zone-file lines: name [ttl] [IN] TYPE value. Use @ for the domain, relative names like _dmarc or selector1._domainkey, and a trailing dot for other domains (e.g. include targets).", "type": "string", "maxLength": 60000 }, "mtaStsPolicy": { "title": "MTA-STS policy file (paste mode, optional)", "type": "string", "maxLength": 10000 } }, "required": [ "domain" ] }, "EmailInfrastructureExplorerResult": { "type": "object", "additionalProperties": false, "required": [ "schemaVersion", "tool", "computedAt", "inputs", "summary", "result", "units", "assumptions", "sources", "warnings", "presentation", "links" ], "properties": { "schemaVersion": { "type": "string", "const": "1.0" }, "tool": { "type": "object", "additionalProperties": false, "required": [ "id", "name", "version" ], "properties": { "id": { "type": "string" }, "name": { "type": "string" }, "version": { "type": "string" } } }, "computedAt": { "type": "string", "format": "date-time" }, "inputs": { "type": "object", "description": "Normalised inputs actually used, including applied defaults." }, "summary": { "type": "string" }, "result": { "type": "object", "additionalProperties": false, "required": [ "domain", "mode", "score", "grade", "scoreItems", "mx", "nullMx", "spf", "dmarc", "dkim", "mtaSts", "tlsRpt", "bimi", "findings", "fixes" ], "properties": { "domain": { "type": "string" }, "mode": { "type": "string", "enum": [ "live", "paste" ] }, "score": { "type": "integer" }, "grade": { "type": "string" }, "scoreItems": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "area", "points", "max", "applicable", "detail" ], "properties": { "area": { "type": "string" }, "points": { "type": "number" }, "max": { "type": "number" }, "applicable": { "type": "boolean" }, "detail": { "type": "string" } } } }, "mx": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "priority", "exchange", "addresses" ], "properties": { "priority": { "type": "integer" }, "exchange": { "type": "string" }, "addresses": { "type": "array", "items": { "type": "string" } } } } }, "nullMx": { "type": "boolean" }, "spf": { "type": "object", "additionalProperties": false, "required": [ "record", "lookups", "voidLookups", "includes" ], "properties": { "record": { "type": [ "string", "null" ] }, "lookups": { "type": "integer" }, "voidLookups": { "type": "integer" }, "includes": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "domain", "depth", "record", "lookups" ], "properties": { "domain": { "type": "string" }, "depth": { "type": "integer" }, "record": { "type": [ "string", "null" ] }, "lookups": { "type": "integer" } } } } } }, "dmarc": { "type": "object", "additionalProperties": false, "required": [ "record", "policy" ], "properties": { "record": { "type": [ "string", "null" ] }, "policy": { "type": [ "string", "null" ] } } }, "dkim": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "selector", "record", "keyType", "bits", "revoked" ], "properties": { "selector": { "type": "string" }, "record": { "type": "string" }, "keyType": { "type": "string" }, "bits": { "type": [ "integer", "null" ] }, "revoked": { "type": "boolean" } } } }, "mtaSts": { "type": "object", "additionalProperties": false, "required": [ "record", "policyFetched", "mode", "mx", "maxAge" ], "properties": { "record": { "type": [ "string", "null" ] }, "policyFetched": { "type": "boolean" }, "mode": { "type": [ "string", "null" ] }, "mx": { "type": "array", "items": { "type": "string" } }, "maxAge": { "type": [ "integer", "null" ] } } }, "tlsRpt": { "type": [ "string", "null" ] }, "bimi": { "type": [ "string", "null" ] }, "findings": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "severity", "area", "finding" ], "properties": { "severity": { "type": "string", "enum": [ "high", "medium", "low", "info" ] }, "area": { "type": "string" }, "finding": { "type": "string" } } } }, "fixes": { "type": "array", "items": { "type": "string" } } } }, "units": { "type": "object", "additionalProperties": { "type": "string" } }, "assumptions": { "type": "array", "items": { "type": "string" } }, "sources": { "type": "array", "items": { "type": "object", "additionalProperties": false, "required": [ "title" ], "properties": { "title": { "type": "string" }, "url": { "type": "string" }, "publisher": { "type": "string" }, "retrievedAt": { "type": "string" }, "note": { "type": "string" } } } }, "warnings": { "type": "array", "items": { "type": "string" } }, "presentation": { "type": "array", "items": { "type": "object" }, "description": "Display blocks used by the human page (same data)." }, "links": { "type": "object", "additionalProperties": false, "required": [ "human", "api", "openapi", "methodology" ], "properties": { "human": { "type": "string", "format": "uri" }, "api": { "type": "string", "format": "uri" }, "openapi": { "type": "string", "format": "uri" }, "methodology": { "type": "string", "format": "uri" } } } } } } } }