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OpenAPI Specification
openapi: 3.2.0
info:
title: 2s — the (most) everything Dns API
version: '1'
summary: The (most) everything API.
description: 'The (most) everything API for AI agents: 575+ pay-per-call endpoints on one origin.'
contact:
name: 2s
url: https://2s.io
email: alley@2s.io
x-logo:
url: https://2s.io/icon-512.png
altText: 2s
x-guidance: 'Pay-per-call REST API for AI agents — hundreds of endpoints returning ground-truth data (US public records, company & legal identifiers, finance/SEC, crypto/web3, security & CVEs, medical codes, weather & geocoding, agriculture, energy, maritime, music, and more). Every endpoint is paid per call in USDC via x402 (Base or Solana) — no API key, no signup. Call any endpoint with no auth to get a 402 PaymentRequirements envelope, sign it (EIP-3009 on Base, partial SPL transfer on Solana), and retry with the PAYMENT-SIGNATURE header. Add ?trial=1 for one free real call per endpoint per hour to test before paying. To discover the right endpoint: GET https://2s.io/api/directory for the full catalog, or GET https://2s.io/api/search/endpoints?q=<natural-language task> for a ranked match. Per-call price is on each operation as x-payment-info (from $0.001). Batch up to 50 calls behind one payment via POST https://2s.io/api/batch/run.'
servers:
- url: https://2s.io
tags:
- name: DNS
paths:
/api/dns/lookup:
get:
tags:
- DNS
summary: Resolve a hostname over public DNS and return parsed records
description: 'Resolve a hostname over public DNS and return parsed records. Query: host (required FQDN), types (comma-separated: A,AAAA,MX,TXT,NS,CAA,SRV,CNAME,PTR,SOA — default A,AAAA,MX,TXT,NS), resolver (cloudflare|google|quad9|opendns, optional). Returns one normalized JSON shape per record type with per-type error pass-through. Reserved/local TLDs (.local, .internal, .invalid, .test, localhost) are rejected. 4s per-query timeout.'
operationId: dns_lookup
deprecated: false
security:
- x402Payment: []
responses:
'200':
description: 'Normalized envelope: items = [DNS result] (query, resolver, durationMs, per-type answers object); total = 1 (single resolution, type-keyed answers are not a homogeneous list).'
content:
application/json:
schema:
type: object
required:
- data
- meta
properties:
data:
type: object
properties:
ok:
type: boolean
enum:
- true
items:
type: array
items:
type: object
properties:
query:
type: string
description: The resolved hostname (normalized, no trailing dot).
resolver:
type: string
nullable: true
description: Resolver IP used; null = runtime default resolver.
durationMs:
type: number
description: Wall-clock query duration in ms (not a DNS record TTL).
answers:
type: array
items:
type: object
properties:
type:
type: string
enum:
- A
- AAAA
- MX
- TXT
- NS
- CAA
- SRV
- CNAME
- PTR
- SOA
records:
type: array
items: {}
description: Parsed records; shape varies by type (strings for NS/TXT/CNAME/PTR, objects for A/AAAA-with-TTL, MX, CAA, SRV, SOA). Empty = no records of that type.
error:
type: object
properties:
code:
type: string
message:
type: string
required:
- code
- message
additionalProperties: false
description: Per-type failure pass-through (absent on success/NODATA).
required:
- type
- records
additionalProperties: false
required:
- query
- resolver
- durationMs
- answers
additionalProperties: false
total:
type: integer
nullable: true
description: Total matching rows upstream; null when unknown.
source:
$ref: '#/components/schemas/Source'
required:
- ok
- items
- total
- source
additionalProperties: false
meta:
$ref: '#/components/schemas/CallMeta'
'400':
$ref: '#/components/responses/BadRequest'
'402':
$ref: '#/components/responses/PaymentRequired'
'405':
$ref: '#/components/responses/MethodNotAllowed'
'500':
$ref: '#/components/responses/ServerError'
'502':
$ref: '#/components/responses/UpstreamError'
x-2s-id: dns.lookup
x-2s-version: null
x-2s-price:
usd: 0.0025
x-2s-accepts:
- x402
x-2s-response-shape: normalized
x-payment-info:
price:
mode: fixed
currency: USD
amount: '0.002500'
protocols:
- x402: {}
parameters:
- name: host
in: query
required: true
description: Hostname to look up.
schema:
type: string
minLength: 1
maxLength: 253
- name: types
in: query
required: false
description: Types.
schema:
type: string
pattern: ^(A|AAAA|MX|TXT|NS|CAA|SRV|CNAME|PTR|SOA)(,(A|AAAA|MX|TXT|NS|CAA|SRV|CNAME|PTR|SOA)){0,9}$
- name: resolver
in: query
required: false
description: Resolver.
schema:
type: string
enum:
- cloudflare
- google
- quad9
- opendns
- $ref: '#/components/parameters/TrialMode'
components:
schemas:
Source:
type: object
description: 'Provenance of the data: upstream provider, source URL, and license.'
properties:
provider:
type: string
description: Upstream data provider.
url:
type: string
description: Source URL or documentation link.
license:
type: string
description: License / usage terms for the data.
CallMeta:
type: object
description: Per-call meta envelope — endpoint id, cost, caller kind, settlement details.
X402PaymentRequiredV2:
type: object
description: x402 v2 PaymentRequired envelope. Pick any entry from accepts[], sign for that rail, retry with the PAYMENT-SIGNATURE header.
required:
- x402Version
- accepts
properties:
x402Version:
type: integer
const: 2
error:
type: string
description: Human-readable reason payment is required.
resource:
type: string
description: The resource URL being purchased.
accepts:
type: array
description: Payment requirement options, one per supported network (Base USDC, Solana USDC).
items:
type: object
required:
- scheme
- network
- amount
- asset
- payTo
- maxTimeoutSeconds
properties:
scheme:
type: string
enum:
- exact
network:
type: string
description: CAIP-2 network id, e.g. "eip155:8453" (Base) or "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp".
amount:
type: string
description: Price in atomic asset units (USDC has 6 decimals).
asset:
type: string
description: Asset contract address / mint.
payTo:
type: string
description: Treasury address to pay.
maxTimeoutSeconds:
type: integer
extra:
type: object
description: 'Rail-specific extras (EVM: EIP-712 domain name/version; Solana: feePayer).'
additionalProperties: true
extensions:
type: object
description: Optional discovery metadata (e.g. bazaar input/output schemas).
additionalProperties: true
responses:
PaymentRequired:
description: Payment required. Body contains the x402 PaymentRequirements envelope with a multi-network accepts array; the per-call price is in accepts[].amount (and on the operation as x-2s-price). Sign for whichever rail you hold USDC on (EIP-3009 for Base, partial SPL transfer for Solana) and retry with the PAYMENT-SIGNATURE header (X-PAYMENT also accepted for v1 clients).
content:
application/json:
schema:
$ref: '#/components/schemas/X402PaymentRequiredV2'
UpstreamError:
description: Upstream provider error.
MethodNotAllowed:
description: Method not allowed — see `Allow` header for the supported method.
ServerError:
description: Internal server error.
BadRequest:
description: Bad request — invalid parameters.
parameters:
TrialMode:
name: trial
in: query
required: false
description: 'Try before you buy. Set to 1 for one free real call per endpoint per hour — no wallet or payment needed — to verify the endpoint before paying. Equivalent to sending the "X-2s-Trial: 1" request header. Works on every endpoint.'
schema:
type: integer
enum:
- 1
securitySchemes:
x402Payment:
type: apiKey
in: header
name: PAYMENT-SIGNATURE
description: 'x402 protocol v2: base64-encoded PaymentPayload. Call any paid endpoint without auth to receive a 402 with a multi-network PaymentRequirements envelope. Sign for either rail: EIP-3009 transferWithAuthorization (Base USDC) OR a partial SPL token transfer (Solana USDC). Retry with PAYMENT-SIGNATURE header. X-PAYMENT is also accepted for v1 buyer clients. See https://x402.org.'