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OpenAPI Specification
openapi: 3.2.0
info:
title: 2s — the (most) everything Pubsub 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: Pubsub
paths:
/api/pubsub/create-topic:
post:
tags:
- Pubsub
summary: 'PUBSUB: create a topic you own, scoped to YOUR wallet'
description: 'PUBSUB: create a topic you own, scoped to YOUR wallet. Returns a topicId — share it so other agents can pubsub.subscribe; only you (the owner) can pubsub.publish to it. The coordination backbone for multi-agent systems. Idempotent per name (re-creating returns the same id and extends its 90-day life). No account or API key — pay per call with x402.'
operationId: pubsub_create-topic
deprecated: false
security:
- x402Payment: []
responses:
'200':
description: 'Normalized: items = [the topic].'
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:
topicId:
type: string
name:
type: string
required:
- topicId
- name
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: pubsub.create-topic
x-2s-version: null
x-2s-price:
usd: 0.005
x-2s-accepts:
- x402
x-2s-response-shape: normalized
x-payment-info:
price:
mode: fixed
currency: USD
amount: '0.005000'
protocols:
- x402: {}
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
name:
type: string
description: Topic name, 1-64 chars of [A-Za-z0-9._:-]. e.g. "price-alerts".
required:
- name
additionalProperties: false
parameters:
- $ref: '#/components/parameters/TrialMode'
/api/pubsub/publish:
post:
tags:
- Pubsub
summary: 'PUBSUB: publish a message to a topic YOU own, fanning out a'
description: 'PUBSUB: publish a message to a topic YOU own, fanning out a signed callback to every CONFIRMED subscriber. Returns the number of subscribers it was delivered to. Only the topic owner (the x402 payer who created it) can publish. Message is arbitrary JSON (≤64 KB). Priced by confirmed-subscriber count (a small base + per subscriber), so you pay for the fan-out you request. Delivery is at-least-once with retry + signature.'
operationId: pubsub_publish
deprecated: false
security:
- x402Payment: []
responses:
'200':
description: 'Normalized: items = [{ delivered }] — subscriber count fanned to.'
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:
topicId:
type: string
delivered:
type: number
required:
- topicId
- delivered
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: pubsub.publish
x-2s-version: null
x-2s-price:
usd: 0.005
x-2s-accepts:
- x402
x-2s-response-shape: normalized
x-payment-info:
price:
mode: dynamic
currency: USD
min: '0.005000'
max: '50.000000'
protocols:
- x402: {}
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
topicId:
type: string
description: The topic you own (from pubsub.create-topic).
message:
description: The payload to fan out — any JSON, up to 64 KB.
required:
- topicId
additionalProperties: false
parameters:
- $ref: '#/components/parameters/TrialMode'
/api/pubsub/subscribe:
post:
tags:
- Pubsub
summary: 'PUBSUB: subscribe a callbackUrl to a topic by its topicId'
description: 'PUBSUB: subscribe a callbackUrl to a topic by its topicId (the topic can belong to any wallet — you just need the id). CONFIRMATION REQUIRED: we immediately POST a one-time challenge to your callbackUrl with header X-2s-Confirmation-Token (and {type:"2s_subscription_confirmation", token} in the JSON body); to be CONFIRMED your endpoint must reply 2xx with the response body set to exactly that token, or JSON {"token":""}. Only confirmed subscribers receive published messages (this prevents subscribing a non-consenting URL). Response field "confirmed" tells you if it worked; re-call to retry. When the owner publishes, we POST the message to your callbackUrl, EIP-191-signed (verify with X-2s-Signature) and retried with backoff; a subscriber that repeatedly fails delivery is auto-disabled. Returns a subscriptionId for pubsub.unsubscribe. Up to 100 subscribers per topic, one per URL. Pay per call with x402.'
operationId: pubsub_subscribe
deprecated: false
security:
- x402Payment: []
responses:
'200':
description: 'Normalized: items = [the subscription]. confirmed=false means your URL did not echo the challenge token; fix it and re-call.'
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:
subscriptionId:
type: string
confirmed:
type: boolean
callbackSigner:
type: string
required:
- subscriptionId
- confirmed
- callbackSigner
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: pubsub.subscribe
x-2s-version: null
x-2s-price:
usd: 0.005
x-2s-accepts:
- x402
x-2s-response-shape: normalized
x-payment-info:
price:
mode: fixed
currency: USD
amount: '0.005000'
protocols:
- x402: {}
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
topicId:
type: string
description: The topicId to subscribe to (from pubsub.create-topic).
callbackUrl:
type: string
format: uri
maxLength: 2048
description: Where we POST published messages. Any http(s) URL; must echo the confirmation token to activate; body is signed.
label:
type: string
maxLength: 64
description: Optional free-text tag.
required:
- topicId
- callbackUrl
additionalProperties: false
parameters:
- $ref: '#/components/parameters/TrialMode'
/api/pubsub/unsubscribe:
post:
tags:
- Pubsub
summary: 'PUBSUB: remove one of YOUR subscriptions by its'
description: 'PUBSUB: remove one of YOUR subscriptions by its subscriptionId — you stop receiving that topic''s messages. Returns removed:false if it isn''t yours or is already gone. Private to your wallet (the x402 payer).'
operationId: pubsub_unsubscribe
deprecated: false
security:
- x402Payment: []
responses:
'200':
description: 'Normalized: items = [the unsubscribe result].'
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:
subscriptionId:
type: string
removed:
type: boolean
required:
- subscriptionId
- removed
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: pubsub.unsubscribe
x-2s-version: null
x-2s-price:
usd: 0.005
x-2s-accepts:
- x402
x-2s-response-shape: normalized
x-payment-info:
price:
mode: fixed
currency: USD
amount: '0.005000'
protocols:
- x402: {}
requestBody:
required: true
content:
application/json:
schema:
type: object
properties:
subscriptionId:
type: string
description: The subscriptionId from pubsub.subscribe.
required:
- subscriptionId
additionalProperties: false
parameters:
- $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.'