WritersLogic Verifiable AI Agent Hub Date Claim Check API
The Date Claim Check API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for date claim check.
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curl "https://apis.io/api/v1/apis/writerslogic-com:writerslogic-com-date-claim-check-api"
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OpenAPI Specification
openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Date Claim Check 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: Date Claim Check
paths:
/api/v1/date-claim-check:
post:
operationId: date_claim_check
summary: Does this date fall on the claimed weekday?
description: 'Checks up to 200 claims ''Monday 2026-12-28'' against the proleptic Gregorian calendar and reports the real weekday, whether the date exists (2026-02-29 does not), and the nearest date carrying the claimed weekday; a claim ''Friday, 13 March'' without a year returns the years in a range where it holds. Built for an agent verifying dates in a document, email or itinerary. Gregorian only (no Julian dates before 1582 reform), no time zones, and it does not guess which year was meant.
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/date-claim-check
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- items
properties:
items:
type: array
minItems: 1
maxItems: 200
items:
type: object
required:
- weekday
properties:
date:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
maxLength: 10
description: YYYY-MM-DD.
monthDay:
type: string
pattern: ^\d{2}-\d{2}$
maxLength: 5
description: MM-DD when the year is unknown; needs fromYear and toYear.
weekday:
type: string
pattern: ^[A-Za-z]{3,9}\.?$
maxLength: 10
description: Monday, Mon, mon ...
fromYear:
type: integer
minimum: 1583
maximum: 2999
toYear:
type: integer
minimum: 1583
maximum: 2999
example:
items:
- date: '2026-12-28'
weekday: Monday
- date: '2027-01-01'
weekday: Thursday
- date: '2026-02-29'
weekday: Sunday
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
date:
type: string
dateExists:
type: boolean
actualWeekday:
type: string
claimedWeekday:
type: string
matches:
type: boolean
nearestMatchingDate:
type: string
matchingYears:
type: array
items:
type: integer
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:
- Date Claim Check
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