WritersLogic Verifiable AI Agent Hub Market Session API
The Market Session API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for market session.
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curl "https://apis.io/api/v1/apis/writerslogic-com:writerslogic-com-market-session-api"
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OpenAPI Specification
openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Market Session API
version: 2.0.0
description: Pay-per-call agents settled in USDC on Base via x402. Every response carries a signed provenance envelope.
contact:
name: WritersLogic
url: https://writerslogic.com/agents
email: agents@writerslogic.com
servers:
- url: https://agents.writerslogic.com
tags:
- name: Market Session
paths:
/api/v1/market-session:
post:
operationId: market_session
summary: Is the exchange in its core session at this instant?
description: 'For up to 50 caller-supplied instants, reports whether the NYSE core session (09:30-16:00 America/New_York, 13:00 on early-close days) is open, the reason when closed (weekend, named holiday, before open, after close), that day''s open and close instants and the next open; or the same for a caller venue (zone, open, close, holidays, early closes). NYSE data is a dated snapshot of nyse.com covering 2026-2028; any instant outside it is `unsupported`. It does not cover pre-market, extended hours, auctions, other exchanges'' calendars, halts or unscheduled closures, and never reads the clock: pass the instant you care about.
Price: 0.005 USDC on Base (x402).'
x-x402-price-usdc: '0.005'
x-x402-amount: '5000'
x-payment-info:
protocols:
- x402
price:
mode: fixed
currency: USD
amount: '0.005'
x-audience: business
x-sample-url: https://agents.writerslogic.com/api/v1/samples/market-session
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- venue
- instants
properties:
venue:
type: string
enum:
- nyse
- caller
instants:
type: array
minItems: 1
maxItems: 50
items:
type: string
pattern: ^\d{4}-\d{2}-\d{2}[Tt ]\d{2}:\d{2}(:\d{2}(\.\d{1,9})?)?(Z|z|[+-]\d{2}:?\d{2})$
maxLength: 36
description: RFC 3339 timestamps with Z or offset.
expect:
type: string
enum:
- open
- closed
description: If given, status is fail for any instant whose state differs.
timeZone:
type: string
pattern: ^[A-Za-z][A-Za-z0-9_+-]*(/[A-Za-z0-9_+-]+){0,2}$
maxLength: 64
description: venue caller only.
open:
type: string
pattern: ^([01]\d|2[0-3]):[0-5]\d$
maxLength: 5
description: venue caller only, local HH:MM.
close:
type: string
pattern: ^([01]\d|2[0-3]):[0-5]\d$
maxLength: 5
description: venue caller only, local HH:MM, after open.
holidays:
type: array
maxItems: 400
items:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
maxLength: 10
description: Extra non-business dates YYYY-MM-DD (company closures, a calendar we do not carry).
weekend:
type: array
maxItems: 6
items:
type: integer
minimum: 0
maximum: 6
description: Non-business weekdays, 0=Sunday..6=Saturday. Default [0, 6]; use [5, 6] for a Friday/Saturday weekend.
earlyCloses:
type: array
maxItems: 100
items:
type: object
required:
- date
- close
properties:
date:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
maxLength: 10
close:
type: string
pattern: ^([01]\d|2[0-3]):[0-5]\d$
maxLength: 5
description: venue caller only.
example:
venue: nyse
instants:
- '2026-11-27T17:30:00Z'
- '2026-11-27T19:30:00Z'
- '2026-07-03T15:00:00Z'
responses:
'200':
description: Paid result with provenance
content:
application/json:
schema:
type: object
properties:
data:
type: object
properties:
status:
type: string
enum:
- pass
- fail
- unknown
- unsupported
description: 'pass: every rule held. fail: a rule was violated (see witnesses). unknown: the input lacks the evidence to decide. unsupported: outside what this engine covers. Missing evidence is never a pass.'
items:
type: array
items:
type: object
properties:
index:
type: integer
instantUtc:
type: string
local:
type: string
state:
type: string
enum:
- open
- closed
reason:
type: string
earlyClose:
type: boolean
sessionOpenUtc:
type: string
sessionCloseUtc:
type: string
nextOpenUtc:
type: string
reason:
type: string
witnesses:
type: array
items:
type: object
properties:
ruleId:
type: string
detail:
type: string
path:
type: string
description: JSON pointer or dotted path into the input.
offset:
type: integer
index:
type: integer
expected:
description: What the rule required.
actual:
description: What the input had.
versions:
type: object
description: Every semantic dependency of this answer (engine, tables and their as-of dates, tokenizer, calendar, rounding profile).
limits:
type: array
items:
type: string
deterministic:
type: boolean
description: 'Always true: pure code, no model.'
_provenance:
type: object
description: C2PA-aligned manifest and W3C VC 2.0 (eddsa-jcs-2022) issued by the hub DID; verify at POST /api/v1/verify-provenance
required:
- data
- _provenance
'400':
description: Invalid request (no payment consumed)
content:
application/json:
schema:
type: object
properties:
error:
type: string
code:
type: string
'401':
description: Invalid X-API-KEY
content:
application/json:
schema:
type: object
properties:
error:
type: string
code:
type: string
'402':
description: Payment required or invalid
content:
application/json:
schema:
type: object
description: x402 v2 PaymentRequired (also base64 in the PAYMENT-REQUIRED header)
properties:
x402Version:
type: integer
error:
type: string
code:
type: string
resource:
type: object
accepts:
type: array
items:
type: object
extensions:
type: object
'502':
description: Upstream failure; the payment is released or not settled
content:
application/json:
schema:
type: object
properties:
error:
type: string
code:
type: string
tags:
- Market Session
components:
securitySchemes:
x402:
type: apiKey
in: header
name: PAYMENT-SIGNATURE
description: x402 v2 payment payload (base64) sent after a 402 challenge
apiKey:
type: apiKey
in: header
name: X-API-KEY