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OpenAPI Specification
openapi: 3.2.0
info:
title: 2s — the (most) everything Census 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: census
paths:
/api/census/demographics:
get:
tags:
- census
summary: US Census ACS 5-year demographics for a state or county
description: US Census ACS 5-year demographics for a state or county. Give a state (2-letter or 2-digit FIPS), optionally a 3-digit county FIPS, and get population, median age, median household income, per-capita income, poverty rate (computed), households, owner-occupancy rate (computed), median home value, and median gross rent. Free, public-domain (US Census Bureau). Complements census.zipcode (ZIP/ZCTA-level) with state- and county-level geography. Authoritative demographic data an LLM cannot recall — for market sizing, site selection, and socioeconomic research.
operationId: census_demographics
deprecated: false
security:
- x402Payment: []
responses:
'200':
description: 'Normalized envelope: items = [one geography demographics object]; total = 1.'
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: object
properties:
state:
type: string
county:
type: string
nullable: true
year:
type: number
required:
- state
- county
- year
additionalProperties: false
geoName:
type: string
nullable: true
population:
type: number
nullable: true
medianAge:
type: number
nullable: true
medianHouseholdIncomeUSD:
type: number
nullable: true
perCapitaIncomeUSD:
type: number
nullable: true
povertyRate:
type: number
nullable: true
households:
type: number
nullable: true
ownerOccupancyRate:
type: number
nullable: true
medianHomeValueUSD:
type: number
nullable: true
medianGrossRentUSD:
type: number
nullable: true
source:
$ref: '#/components/schemas/Source'
note:
type: string
required:
- query
- geoName
- population
- medianAge
- medianHouseholdIncomeUSD
- perCapitaIncomeUSD
- povertyRate
- households
- ownerOccupancyRate
- medianHomeValueUSD
- medianGrossRentUSD
- source
- note
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':
$ref: '#/components/responses/UpstreamError'
x-2s-id: census.demographics
x-2s-version: null
x-2s-price:
usd: 0.0027
x-2s-accepts:
- x402
x-2s-response-shape: normalized
x-payment-info:
price:
mode: fixed
currency: USD
amount: '0.002700'
protocols:
- x402: {}
parameters:
- name: state
in: query
required: true
description: 2-letter state code or 2-digit FIPS.
schema:
type: string
minLength: 2
maxLength: 2
- name: county
in: query
required: false
description: County name to filter by.
schema:
type: string
pattern: ^\d{3}$
- name: year
in: query
required: false
description: Four-digit calendar year.
schema:
type: integer
minimum: 2010
maximum: 2100
- $ref: '#/components/parameters/TrialMode'
/api/census/zipcode:
get:
tags:
- census
summary: US Census ACS 5-year demographics for a ZIP code (ZCTA)
description: US Census ACS 5-year demographics for a ZIP code (ZCTA). Returns population, median age, median household income, poverty rate, household composition, race + ethnicity breakdown, education attainment, workforce (with computed unemployment rate), and housing (with computed owner-occupancy rate and median rent/home value). Backed by ~33k ZCTAs pre-ingested from api.census.gov; refreshed annually. Public-domain US government data.
operationId: census_zipcode
deprecated: false
security:
- x402Payment: []
responses:
'200':
description: 'Normalized envelope: items = [demographics] (one ZCTA: population, age, income, poverty, households, race/ethnicity, education, workforce, housing — with computed rates); total = 1. 404 if the ZIP has no ZCTA coverage.'
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:
zip:
type: string
acsYear:
type: number
description: ACS 5-year vintage end year.
acsRelease:
type: string
description: Human-readable release label, e.g. "ACS 5-year 2018-2022".
population:
type: number
nullable: true
medianAge:
type: number
nullable: true
income:
type: object
properties:
medianHouseholdUSD:
type: number
nullable: true
required:
- medianHouseholdUSD
additionalProperties: false
poverty:
type: object
properties:
universe:
type: number
nullable: true
countBelow:
type: number
nullable: true
rateBelow:
type: number
nullable: true
description: Poverty rate as a percent (computed).
required:
- universe
- countBelow
- rateBelow
additionalProperties: false
households:
type: object
properties:
total:
type: number
nullable: true
singlePerson:
type: number
nullable: true
required:
- total
- singlePerson
additionalProperties: false
race:
type: object
properties:
white:
type: number
nullable: true
black:
type: number
nullable: true
americanIndianAlaskaNative:
type: number
nullable: true
asian:
type: number
nullable: true
nativeHawaiianPacificIslander:
type: number
nullable: true
other:
type: number
nullable: true
twoOrMore:
type: number
nullable: true
required:
- white
- black
- americanIndianAlaskaNative
- asian
- nativeHawaiianPacificIslander
- other
- twoOrMore
additionalProperties: false
ethnicity:
type: object
properties:
hispanicOrLatino:
type: number
nullable: true
required:
- hispanicOrLatino
additionalProperties: false
education:
type: object
properties:
universe:
type: number
nullable: true
highSchool:
type: number
nullable: true
bachelors:
type: number
nullable: true
masters:
type: number
nullable: true
professional:
type: number
nullable: true
doctorate:
type: number
nullable: true
pctBachelorsOrHigher:
type: number
nullable: true
description: Percent of 25+ adults with a bachelor's or higher (computed).
required:
- universe
- highSchool
- bachelors
- masters
- professional
- doctorate
- pctBachelorsOrHigher
additionalProperties: false
workforce:
type: object
properties:
laborForceSize:
type: number
nullable: true
unemployed:
type: number
nullable: true
unemploymentRate:
type: number
nullable: true
description: Unemployment rate as a percent (computed).
required:
- laborForceSize
- unemployed
- unemploymentRate
additionalProperties: false
housing:
type: object
properties:
units:
type: number
nullable: true
occupied:
type: number
nullable: true
ownerOccupied:
type: number
nullable: true
renterOccupied:
type: number
nullable: true
medianHomeValueUSD:
type: number
nullable: true
medianGrossRentUSD:
type: number
nullable: true
pctOwnerOccupied:
type: number
nullable: true
description: Owner-occupancy rate as percent of occupied units (computed).
required:
- units
- occupied
- ownerOccupied
- renterOccupied
- medianHomeValueUSD
- medianGrossRentUSD
- pctOwnerOccupied
additionalProperties: false
updatedAt:
type: string
required:
- zip
- acsYear
- acsRelease
- population
- medianAge
- income
- poverty
- households
- race
- ethnicity
- education
- workforce
- housing
- updatedAt
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':
$ref: '#/components/responses/UpstreamError'
x-2s-id: census.zipcode
x-2s-version: null
x-2s-price:
usd: 0.0025
x-2s-accepts:
- x402
x-2s-response-shape: normalized
x-payment-info:
price:
mode: fixed
currency: USD
amount: '0.002500'
protocols:
- x402: {}
parameters:
- name: zip
in: query
required: true
description: US ZIP code.
schema:
type: string
pattern: ^\d{5}$
- $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.'