FirstSales Domain API
Domain intelligence (age, records, subdomains).
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OpenAPI Specification
openapi: 3.2.0
info:
title: Firstsales Io Domain API
version: 1.0.0
contact:
name: FirstSales Support
email: firstsales@support.communicate.so
url: https://firstsales.io
license:
name: Terms of Service
url: https://firstsales.io/terms-of-service/
termsOfService: https://firstsales.io/terms-of-service/
x-apiVersioning:
strategy: url-path
current: v1
pattern: https://firstsales.io/api/v1/{operation}
policyUrl: https://firstsales.io/developers/#versioning
note: A breaking change ships under a new prefix (/api/v2/); v1 keeps its contract. The unprefixed /api/{operation} form is an unversioned alias of the current version and may change without notice - call the /api/v1/ form.
x-deprecationPolicy:
minimumNoticeDays: 180
signalling: 'A deprecated version''s responses carry Deprecation: true and a Sunset header with the retirement date (RFC 8594), plus a Link rel="deprecation" to the migration notes.'
announcement: https://firstsales.io/developers/#deprecation-policy
policyUrl: https://firstsales.io/developers/#deprecation-policy
currentlyDeprecated: []
description: 'Operations tagged Domain across 2 of this provider''s published API definitions: firstsales-io-openapi.json, openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://firstsales.io
description: Production
security: []
tags:
- name: Domain
description: Domain intelligence (age, records, subdomains).
paths:
/api/v1/domain/age:
post:
operationId: getDomainAge
summary: Get a domain's registration age and expiration via RDAP
description: 'Queries RDAP (the modern WHOIS replacement) for registration date, expiration date, last-updated date, registrar, and status, and computes age in days/months/years. Use this to flag newly-registered domains, a common spam/fraud signal. Rate limit: 10 requests/minute per IP.'
tags:
- Domain
security: []
x-rateLimit:
limit: 10
windowSeconds: 60
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
domain:
type: string
required:
- domain
responses:
'200':
description: Domain age/registration details.
content:
application/json:
schema:
$ref: '#/components/schemas/DomainAgeResult'
'400':
description: Invalid request — bad input, missing field, or malformed value.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'404':
description: Domain not found in the RDAP registry.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'429':
description: Rate limit exceeded for this endpoint. Wait Retry-After seconds and retry.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
Retry-After:
description: Seconds to wait before retrying.
schema:
type: integer
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'500':
description: Unexpected server error.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
servers:
- url: https://firstsales.io
description: Production
/api/v1/domain/dns-records:
post:
operationId: getDomainDnsRecords
summary: Fetch every DNS record type for a domain in one call
description: 'Queries A, AAAA, MX, NS, TXT, SOA, and CNAME records in parallel and returns them flattened, with a per-type summary count. Use this for a full DNS snapshot instead of calling dns/check once per record type. Rate limit: 10 requests/minute per IP.'
tags:
- Domain
security: []
x-rateLimit:
limit: 10
windowSeconds: 60
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
domain:
type: string
required:
- domain
responses:
'200':
description: All discovered DNS records for the domain.
content:
application/json:
schema:
$ref: '#/components/schemas/DnsRecordsResult'
'400':
description: Invalid request — bad input, missing field, or malformed value.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'404':
description: Domain does not exist or has no DNS records.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'429':
description: Rate limit exceeded for this endpoint. Wait Retry-After seconds and retry.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
Retry-After:
description: Seconds to wait before retrying.
schema:
type: integer
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'500':
description: Unexpected server error.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
servers:
- url: https://firstsales.io
description: Production
/api/v1/domain/subdomains:
post:
operationId: findSubdomains
summary: Discover subdomains via Certificate Transparency logs
description: 'Queries crt.sh Certificate Transparency logs for every certificate issued for the domain and extracts unique subdomains from SAN entries. Passive/OSINT technique — no active scanning. Slower than other domain checks (crt.sh can be slow) and more tightly rate-limited: 5 requests/minute per IP.'
tags:
- Domain
security: []
x-rateLimit:
limit: 5
windowSeconds: 60
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
domain:
type: string
required:
- domain
responses:
'200':
description: Discovered subdomains.
content:
application/json:
schema:
$ref: '#/components/schemas/SubdomainsResult'
'400':
description: Invalid request — bad input, missing field, or malformed value.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'429':
description: Rate limit exceeded for this endpoint. Wait Retry-After seconds and retry.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
Retry-After:
description: Seconds to wait before retrying.
schema:
type: integer
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'500':
description: Unexpected server error.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'502':
description: Failed to query Certificate Transparency logs (crt.sh unavailable).
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
'504':
description: Certificate Transparency lookup timed out.
headers:
RateLimit-Limit:
description: Requests allowed in the current window.
schema:
type: integer
RateLimit-Remaining:
description: Requests still available in the current window.
schema:
type: integer
RateLimit-Reset:
description: Seconds until the current window resets.
schema:
type: integer
RateLimit-Policy:
description: Policy in the form "<limit>;w=<window seconds>".
schema:
type: string
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
servers:
- url: https://firstsales.io
description: Production
components:
schemas:
Error:
type: object
description: Shared error envelope used by public endpoints and the rate-limit wrapper. Mail-tester handler errors use MailTesterError.
properties:
error:
type: string
description: Machine-readable error code, e.g. `invalid_input`.
message:
type: string
description: Human-readable explanation.
hint:
type: string
description: How to fix the request.
required:
- error
- message
- hint
DnsRecordsResult:
type: object
properties:
domain:
type: string
records:
type: array
items:
type: object
properties:
type:
type: string
enum:
- A
- AAAA
- MX
- NS
- TXT
- SOA
- CNAME
value:
type: string
priority:
type: number
ttl:
type: number
required:
- type
- value
summary:
type: object
description: 'Count of records per type, e.g. { A: 1, MX: 2 }.'
additionalProperties:
type: number
totalRecords:
type: number
required:
- domain
- records
- summary
- totalRecords
SubdomainsResult:
type: object
properties:
domain:
type: string
subdomains:
type: array
items:
type: string
count:
type: number
source:
type: string
enum:
- Certificate Transparency (crt.sh)
required:
- domain
- subdomains
- count
- source
DomainAgeResult:
type: object
properties:
domain:
type: string
registrationDate:
type:
- string
- 'null'
expirationDate:
type:
- string
- 'null'
lastUpdated:
type:
- string
- 'null'
ageInDays:
type:
- number
- 'null'
ageInMonths:
type:
- number
- 'null'
ageInYears:
type:
- number
- 'null'
registrar:
type:
- string
- 'null'
status:
type: array
items:
type: string
name:
type: string
required:
- domain
- registrationDate
- expirationDate
- lastUpdated
- ageInDays
- ageInMonths
- ageInYears
- registrar
- status
- name
x-refined-from:
- firstsales-io-openapi.json
- openapi.json
x-apiVersioning:
strategy: url-path
current: v1
pattern: https://firstsales.io/api/v1/{operation}
policyUrl: https://firstsales.io/developers/#versioning
note: A breaking change ships under a new prefix (/api/v2/); v1 keeps its contract. The unprefixed /api/{operation} form is an unversioned alias of the current version and may change without notice - call the /api/v1/ form.
x-deprecationPolicy:
minimumNoticeDays: 180
signalling: 'A deprecated version''s responses carry Deprecation: true and a Sunset header with the retirement date (RFC 8594), plus a Link rel="deprecation" to the migration notes.'
announcement: https://firstsales.io/developers/#deprecation-policy
policyUrl: https://firstsales.io/developers/#deprecation-policy
currentlyDeprecated: []