The Week Number API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for week number.
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openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Week Number 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: Week Number
paths:
/api/v1/week-number:
post:
operationId: week_number
summary: Week number and week-year for dates under ISO 8601, US or custom rules (53-week…
description: 'Returns the week number, week-year, number of weeks in that year and the week''s first and last day for up to 200 dates under ISO 8601 (Monday start, week 1 holds 4 January), the US convention (Sunday start, week 1 holds 1 January) or a custom weekStart/minimalDays rule, and checks an asserted week or week-year (2027-01-01 is ISO 2026-W53). Built for an agent reading or writing week-based dates in reports, schedules and file names. Fiscal week calendars are handled by fiscal-period; it does not decide which convention a document used.
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/week-number
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- system
- items
properties:
system:
type: string
enum:
- iso
- us
- custom
description: 'iso: weekStart Monday, minimalDays 4. us: weekStart Sunday, minimalDays 1. custom: give weekStart and minimalDays.'
weekStart:
type: integer
minimum: 0
maximum: 6
description: 0=Sunday..6=Saturday (custom).
minimalDays:
type: integer
minimum: 1
maximum: 7
description: Days of the new year the first week must contain (custom).
items:
type: array
minItems: 1
maxItems: 200
items:
type: object
required:
- date
properties:
date:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
maxLength: 10
claimedWeek:
type: integer
minimum: 1
maximum: 54
claimedWeekYear:
type: integer
minimum: 1000
maximum: 3000
example:
system: iso
items:
- date: '2027-01-01'
claimedWeek: 53
claimedWeekYear: 2026
- date: '2026-12-31'
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
weekYear:
type: integer
week:
type: integer
weeksInYear:
type: integer
weekStart:
type: string
weekEnd:
type: string
label:
type: string
matches:
type: boolean
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:
- Week Number
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