The Age Threshold API from WritersLogic Verifiable AI Agent Hub — 1 operation(s) for age threshold.
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openapi: 3.2.0
info:
title: WritersLogic Verifiable AI Agent Hub Age Threshold 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: Age Threshold
paths:
/api/v1/age-threshold:
post:
operationId: age_threshold
summary: Age in complete years on a date and the exact dates a minimum or maximum age is…
description: 'For up to 100 people, computes age in complete years and months on a caller asOf date, the date they reach each minimum age (the birthday) and the first day they exceed each maximum age, and checks min/max age requirements; 29 February births need a declared common-year rule (28 February or 1 March) because jurisdictions differ. Built for an agent checking eligibility (18+, under 65, 21 to buy). It uses the birth date as a calendar date with no time zone or time of day, does not know a jurisdiction''s age-reckoning rules (East Asian age, ''age at last birthday'' contracts) and never reads the clock.
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/age-threshold
security:
- x402: []
- apiKey: []
requestBody:
required: true
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- asOf
- items
properties:
asOf:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
maxLength: 10
leapDayRule:
type: string
enum:
- feb-28
- mar-1
description: In common years a 29 February birthday is observed on 28 February or on 1 March depending on the legal context you apply; you must choose. Required if any birth date is 29 February.
items:
type: array
minItems: 1
maxItems: 100
items:
type: object
required:
- birthDate
properties:
id:
type: string
maxLength: 64
birthDate:
type: string
pattern: ^\d{4}-\d{2}-\d{2}$
maxLength: 10
minAgeYears:
type: integer
minimum: 0
maximum: 150
maxAgeYears:
type: integer
minimum: 0
maximum: 150
description: 'Inclusive: age must still be at most this many complete years.'
example:
asOf: '2026-11-04'
items:
- id: p1
birthDate: '2008-11-04'
minAgeYears: 18
- id: p2
birthDate: '2008-11-05'
minAgeYears: 18
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
id:
type: string
ageYears:
type: integer
ageMonths:
type: integer
nextBirthday:
type: string
minAgeReachedOn:
type: string
maxAgeExceededOn:
type: string
meetsMin:
type: boolean
meetsMax:
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:
- Age Threshold
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